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Chess and Math: A Closer Look at the Knight's Tour

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The Knight’s tour problem

Backtracking is an algorithmic paradigm that tries different solutions until finds a solution that “works”. Problems that are typically solved using the backtracking technique have the following property in common. These problems can only be solved by trying every possible configuration and each configuration is tried only once. A Naive solution for these problems is to try all configurations and output a configuration that follows given problem constraints. Backtracking works incrementally and is an optimization over the Naive solution where all possible configurations are generated and tried. For example, consider the following Knight’s Tour problem. 

Problem Statement: Given a N*N board with the Knight placed on the first block of an empty board. Moving according to the rules of chess knight must visit each square exactly once. Print the order of each cell in which they are visited.

The path followed by Knight to cover all the cells Following is a chessboard with 8 x 8 cells. Numbers in cells indicate the move number of Knight. 

Let us first discuss the Naive algorithm for this problem and then the Backtracking algorithm.

Naive Algorithm for Knight’s tour   The Naive Algorithm is to generate all tours one by one and check if the generated tour satisfies the constraints. 

Backtracking works in an incremental way to attack problems. Typically, we start from an empty solution vector and one by one add items (Meaning of item varies from problem to problem. In the context of Knight’s tour problem, an item is a Knight’s move). When we add an item, we check if adding the current item violates the problem constraint, if it does then we remove the item and try other alternatives. If none of the alternatives works out then we go to the previous stage and remove the item added in the previous stage. If we reach the initial stage back then we say that no solution exists. If adding an item doesn’t violate constraints then we recursively add items one by one. If the solution vector becomes complete then we print the solution.

Backtracking Algorithm for Knight’s tour  

Following is the Backtracking algorithm for Knight’s tour problem. 

Following are implementations for Knight’s tour problem. It prints one of the possible solutions in 2D matrix form. Basically, the output is a 2D 8*8 matrix with numbers from 0 to 63 and these numbers show steps made by Knight.   

Time Complexity :  There are N 2 Cells and for each, we have a maximum of 8 possible moves to choose from, so the worst running time is O(8 N^2 ).

Auxiliary Space: O(N 2 )

Important Note: No order of the xMove, yMove is wrong, but they will affect the running time of the algorithm drastically. For example, think of the case where the 8th choice of the move is the correct one, and before that our code ran 7 different wrong paths. It’s always a good idea a have a heuristic than to try backtracking randomly. Like, in this case, we know the next step would probably be in the south or east direction, then checking the paths which lead their first is a better strategy.

Note that Backtracking is not the best solution for the Knight’s tour problem. See the below article for other better solutions. The purpose of this post is to explain Backtracking with an example.  Warnsdorff’s algorithm for Knight’s tour problem

References:  http://see.stanford.edu/materials/icspacs106b/H19-RecBacktrackExamples.pdf   http://www.cis.upenn.edu/~matuszek/cit594-2009/Lectures/35-backtracking.ppt   http://mathworld.wolfram.com/KnightsTour.html   http://en.wikipedia.org/wiki/Knight%27s_tour    

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“Chess is a war over the board. The object is to crush the opponent’s mind.” – Robert Fischer

Knight’s Tour: The famous mathematical problem

Chess is a game of strategy and foresight, demanding players to think several moves ahead to outmaneuver their opponents. Among the numerous puzzles and challenges that arise from the complexity of chess, the Knight’s Tour Problem stands out as a particularly fascinating conundrum. The Knight’s Tour is a puzzle that involves moving a knight on a chessboard in such a way that it visits each square exactly once.

The Knight’s Tour Problem is a mathematical challenge that revolves around finding a specific sequence of moves for a knight on a chessboard. It has become a popular problem assigned to computer science students, who are tasked with developing programs to solve it. The variations of the Knight’s Tour Problem go beyond the standard 8×8 chessboard, including different sizes and irregular, non-rectangular boards.

If you’re looking to find your own solution to the Knight’s Tour Problem, there is a straightforward approach known as Warnsdorff’s rule . Warnsdorff’s rule serves as a heuristic for discovering a single knight’s tour. The rule dictates that the knight should always move to the square from which it will have the fewest possible subsequent moves. In this calculation, any moves that would revisit a square already visited are not counted. By adhering to Warnsdorff’s rule, you can systematically guide the knight across the chessboard and ultimately find a knight’s tour.

Modern computers have significantly contributed to the exploration of the Knight’s Tour Problem. Through advanced algorithms and computational power, researchers have been able to tackle larger chessboards and refine existing solutions. However, finding a general solution that works for all chessboard sizes remains elusive.

In conclusion, the Knight’s Tour Problem continues to captivate mathematicians, chess players, and computer scientists alike. Its unique combination of chess strategy, mathematical intricacy, and computational challenges makes it a fascinating puzzle to explore. While the search for a comprehensive solution is ongoing, the journey towards unraveling the mysteries of the Knight’s Tour Problem offers valuable insights into the world of mathematics, algorithms, and the boundless potential of human intellect.

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What is the Knight’s Tour problem?

Answered by Michael Weatherspoon

The Knight’s Tour problem is a fascinating puzzle that has intrigued chess enthusiasts and mathematicians for centuries. As a chess grandmaster, I have encountered this problem numerous times and have marveled at its complexity. Allow me to explain in detail what the Knight’s Tour problem entails and why it has captured the imagination of many.

At its core, the Knight’s Tour problem is a variation of the general Hamiltonian path problem in graph theory. In simpler terms, it involves finding a sequence of moves for a knight on a chessboard such that the knight visits every square exactly once. The knight follows the standard moves of a knight in chess, which means it can move in an L-shape, either two squares horizontally and one square vertically or two squares vertically and one square horizontally.

The objective of the Knight’s Tour problem can be twofold. Firstly, one can aim to find an open tour, where the knight starts on one square and ends on another, without revisiting any square in between. Secondly, one can strive to find a closed tour, where the knight starts and ends on the same square, forming a closed loop on the chessboard. While finding an open tour is challenging enough, finding a closed tour is even more difficult and is equivalent to solving the Hamiltonian cycle problem.

The allure of the Knight’s Tour problem lies in its seemingly simple premise but its intricate nature. It appears as a straightforward task to navigate the knight across the chessboard, but as the board size increases, the complexity grows exponentially. The number of possible knight’s tours on an n x n chessboard is immense, making it a true test of problem-solving skills and mathematical insight.

To better understand the intricacies of the Knight’s Tour problem, let’s delve into its connection with the Hamiltonian path problem. The Hamiltonian path problem involves finding a path that visits every vertex of a graph exactly once. In the context of the chessboard, each square represents a vertex, and the knight’s moves correspond to the edges of the graph. Thus, finding a Knight’s Tour is essentially finding a Hamiltonian path on a modified chessboard graph.

Interestingly, unlike the general Hamiltonian path problem, the Knight’s Tour problem can be solved in linear time. This means that as the chessboard size increases, the time required to find a solution does not grow exponentially. However, this does not imply that finding a Knight’s Tour is easy or trivial. The efficient algorithms developed for solving the Knight’s Tour problem utilize various heuristics and optimizations to minimize the computational complexity.

In my personal experience as a chess grandmaster, I have encountered the Knight’s Tour problem in various contexts. It has been a topic of discussion among fellow chess players, a challenge in puzzle books and magazines, and even a source of inspiration for artistic interpretations. Solving the Knight’s Tour not only requires logical thinking and strategic planning but also a deep understanding of the knight’s movement patterns.

The Knight’s Tour problem is a captivating puzzle that involves finding a sequence of moves for a knight on a chessboard such that it visits every square exactly once. It is a variation of the Hamiltonian path problem and can be approached with the objective of finding an open or closed tour. While the problem can be solved in linear time, its complexity grows exponentially with the chessboard size. As a chess grandmaster, I have come to appreciate the intricate nature of the Knight’s Tour problem and its ability to challenge and captivate the minds of chess enthusiasts and mathematicians alike.

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The knight's tour.

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A classic chess problem is to find a sequence of knight moves that visits each square exactly once. Start by placing the knight anywhere on the board, then drag the step slider to see a knight's tour, either as a broken line path or by numbering the squares in order.

Contributed by: Jay Warendorff   (September 2018) Open content licensed under CC BY-NC-SA

Based on and extending a program at Knight's tour .

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Jay Warendorff "The Knight's Tour" http://demonstrations.wolfram.com/TheKnightsTour/ Wolfram Demonstrations Project Published: September 5 2018

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The Knight’s Tour

The  knight’s tour problem  is the mathematical problem of finding a knight’s tour, and probably making knight the most interesting piece on the chess board. The knight visits every square exactly once, if the knight ends on a square that is one knight’s move from the beginning square (so that it could tour the board again immediately, following the same path), the tour is closed; otherwise, it is open.

The knight’s tour problem is an instance of the more general Hamiltonian path problem in graph theory. The problem of finding a closed knight’s tour is similarly an instance of the Hamiltonian cycle problem. Unlike the general Hamiltonian path problem, the knight’s tour problem can be solved in linear time.

Hamiltonian Path Problem

In Graph Theory, a graph is usually defined to be a collection of nodes or vertices and the set of edges which define which nodes are connected with each other. So we use a well known notation of representing a graph G = (V,E) where  V = { v 1 , v 2 , v 3 , … , v n }  and E = {(i, j)|i ∈ V and j ∈ V and i and j is connected}.

Hamiltonian Path is defined to be a single path that visits every node in the given graph, or a permutation of nodes in such a way that for every adjacent node in the permutation there is an edge defined in the graph. Notice that it does not make much sense in repeating the same paths. In order to avoid this repetition, we permute with |V| C 2 combinations of starting and ending vertices.

Simple way of solving the Hamiltonian Path problem would be to permutate all possible paths and see if edges exist on all the adjacent nodes in the permutation. If the graph is a complete graph, then naturally all generated permutations would quality as a Hamiltonian path.

For example. let us find a Hamiltonian path in graph G = (V,E) where V = {1,2,3,4} and E = {(1,2),(2,3),(3,4)}. Just by inspection, we can easily see that the Hamiltonian path exists in permutation 1234. The given algorithm will first generate the following permutations based on the combinations: 1342 1432 1243 1423 1234 1324 2143 2413 2134 2314 3124 3214

The number that has to be generated is ( |V| C 2 ) (|V| – 2)!

Schwenk proved that for any  m  ×  n  board with  m  ≤  n , a closed knight’s tour is always possible  unless  one or more of these three conditions are met:

• m  and  n  are both odd
• m  = 1, 2, or 4
• m  = 3 and  n  = 4, 6, or 8.

Cull and Conrad proved that on any rectangular board whose smaller dimension is at least 5, there is a (possibly open) knight’s tour.

Neural network solutions

The neural network is designed such that each legal knight’s move on the chessboard is represented by a neuron. Therefore, the network basically takes the shape of the  knight’s graph  over an n×n chess board. (A knight’s graph is simply the set of all knight moves on the board)

Each neuron can be either “active” or “inactive” (output of 1 or 0). If a neuron is active, it is considered part of the solution to the knight’s tour. Once the network is started, each active neuron is configured so that it reaches a “stable” state if and only if it has exactly two neighboring neurons that are also active (otherwise, the state of the neuron changes). When the entire network is stable, a solution is obtained. The complete transition rules are as follows:

where t represents time (incrementing in discrete intervals), U(N i,j ) is the state of the neuron connecting square i to square j, V(N i,j ) is the output of the neuron from i to j, and G(N i,j ) is the set of “neighbors” of the neuron (all neurons that share a vertex with N i,j ).

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Knight's tour problem

What is knight's tour problem.

In the knight's tour problem, we are given with an empty chess board of size NxN, and a knight. In chess, the knight is a piece that looks exactly like a horse. Assume, it can start from any location on the board. Now, our task is to check whether the knight can visit all of the squares on the board or not. When it can visit all of the squares, then print the number of jumps needed to reach that location from the starting point.

There can be two ways in which a knight can finish its tour. In the first way, the knight moves one step and returns back to the starting position forming a loop which is called a closed tour . In the second way i.e. the open tour , it finishes anywhere in the board.

For a person who is not familiar with chess, note that the knight moves in a special manner. It can move either two squares horizontally and one square vertically or two squares vertically and one square horizontally in each direction. So, the complete movement looks like English letter 'L' .

Suppose the size of given chess board is 8 and the knight is at the top-left position on the board. The next possible moves are shown below −

Each cell in the above chess board holds a number, that indicates where to start and in how many moves the knight will reach a cell. The final values of the cell will be represented by the below matrix −

Remember, this problem can have multiple solutions, the above matrix is one possible solution.

One way to solve the knight's tour problem is by generating all the tours one by one and then checking if they satisfy the specified constraint or not. However, it is time consuming and not an efficient way.

Backtracking Approach to Solve Knight's tour problem

The other way to solve this problem is to use backtracking. It is a technique that tries different possibilities until a solution is found or all options are tried. It involves choosing a move, making it, and then recursively trying to solve the rest of the problem. If the current move leads to a dead end, we backtrack and undo the move, then try another one.

To solve the knight's tour problem using the backtracking approach, follow the steps given below −

Start from any cell on the board and mark it as visited by the knight.

Move the knight to a valid unvisited cell and mark it visited. From any cell, a knight can take a maximum of 8 moves.

If the current cell is not valid or not taking to the solution, then backtrack and try other possible moves that may lead to a solution.

Repeat this process until the moves of knight are equal to 8 x 8 = 64.

In the following example, we will practically demonstrate how to solve the knight's tour problem.

Knight's Tour Challenge

How to play.

This "game" is basically an implementation of Knight's Tour problem.

You have to produce the longest possible sequence of moves of a chess knight, while visiting squares on the board only once. This sequence is called "tour". If your tour visits every square, then you have achieved a full tour. If you have achieved a full tour and from your last position you could move to your initial square, then you have achieved a closed full tour.

Currently occupied square is highlighted in pale blue, while possible moves are shown with pale green. Click on the currently occupied square to undo.

The Knight’s Tour

January 14, 2019

by WIM Alexey Root, PhD

From December 27-30, 2018, I attended the Pan-American Intercollegiate Team Chess Championships (Pan-Am). The Pan-Am is in different locations each year. In 2017, the tournament was in Columbus, Ohio; at the end of 2019, the Pan-Am will be in Charlotte, North Carolina. At the end of 2018, the Pan-Am was in San Francisco and organized by BayAreaChess. Webster University, coached by Grandmaster Susan Polgar, won the 2018 Pan-Am.

The top chess schools send multiple teams to the Pan-Am to increase their chances to qualify for the President’s Cup (the “Final Four of College Chess”). Webster’s “A” team finished with 5.5 of 6 match points , ahead of The University of Texas at Dallas (“A” team), Webster’s “B” team, and Harvard University, which each scored 5 of 6 match points. Of the four teams with 4.5 of 6 match points, the one with the best tiebreaks was the “A” team from The University of Texas Rio Grande Valley (UTRGV). So UTRGV will join Webster, UT Dallas, and Harvard in the President’s Cup, as each school can send just one team to the President’s Cup. Harvard’s qualifying was especially noteworthy, as Harvard had just one team in the Pan-Am and, unlike the three other schools qualifying for the 2019 President’s Cup, does not offer chess scholarships. You can read about last year’s President’s Cup here . The upcoming President’s Cup will be held April 6-7, 2019 .

What is the Knight’s Tour?

Other than the Pan-Am hopping around the United States (Columbus, San Francisco, Charlotte) like a super-powered knight, why is this column about the knight’s tour? The knight’s tour is recommended by Pan-Am winning coach Susan Polgar. In her free Chess Training Guide for Parents and Teachers , Susan Polgar wrote, “Try to jump with the Knight from one square to another covering all 64 squares on the chess board, landing only once on each square.” When I taught BayAreaChess students, some taking their first chess class and others rated up to 1000, I included the knight’s tour in my morning session on December 27. The photo is of me (pictured on the left), the students, and Grandmaster Atanas Kolev and his wife Natalia (pictured right), who taught the students for the other sessions of the December 26-28 camp. In the photo, the students are holding copies of my 2016 book Prepare With Chess Strategy .

For my first activity on December 27, I taught the “blindfold square game” from my 2006 book, Children and Chess: A Guide for Educators . For that game, one child names a square (such as “e4”) and another child, who is blindfolded or keeps their eyes shut, guesses the color of the square (“white”). Even beginners have a 50% chance to be right on the guess.

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For those students who wanted more of a challenge, I asked them to close their eyes and tell how they would move a knight around the board. For example, a blindfolded student would say, “I want to move my knight from g1, to f3, to g5, to f7” and so forth, until they lost track of where to move the knight next. As a follow-up activity, each child got blank chess diagrams and a pencil. Each child wrote “1” on the square they wanted to start their knight, “2” where it would go next, “3” on the next square, and so forth. The goal was writing “64,” meaning that the knight would have visited each square on the board once and only once. The students got multiple diagrams so that when their knights got stuck they could start again. Each student would again write “1, 2, 3” and so forth, with each number being a knight’s move away from the previous number, for a new knight on a new diagram.

Beginners and more experienced players can enjoy this activity. Try it yourself; any score above 50 before your knight gets stuck (no squares to go to that haven’t already been marked off) is a great first attempt!

Alexey Root is a Woman International Master and the 1989 U.S. Women's chess champion. Her peak US Chess rating was 2260. She has a PhD in education from UCLA. You can find her books on chess on Amazon.com .

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Chess: Gukesh, 17, shocks favourites to become youngest challenger for title

The Chennai teenager won the Candidates by just half a point and will take on China’s Ding Liren for the world crown in a 14-game series later this year

Gukesh Dommaraju became, at 17, the youngest ever Candidates ­ winner and world championship challenger on Sunday after edging out the favourites Fabiano Caruana, Hikaru Nakamura and Ian Nepomniachtchi in a marathon six-hour final round in Toronto.

Gukesh will now meet the holder, China’s Ding Liren, in a 14-game series for the world crown from 20 November to 15 December. The world No 1, Norway’s Magnus Carlsen, abdicated his title in 2023 after a 10-year reign.

The Chennai teenager started the 14th and final round half a point ahead of his three rivals, and had the better of a draw with Nakamura, the USA’s world No 3. Caruana, the USA’s world No 2, had the chance to force a tie and a speed playoff, but failed to convert his winning position against Russia’s Nepomniachtchi. Their game lasted 109 moves and six hours before Caruana abandoned his attempts to make progress in what was by then a dead drawn ending.

The American and the Russian have fought for the crown for the best part of a decade, and their mutual disappointment brought out a camaraderie between them, as shown in a video of the final moments of their game. “Really sorry,” says Nepomniachtchi. “My fault,” replies Caruana.

Final leading scores were Gukesh 9/14, Caruana, Nakamura and Nepomniachtchi all 8.5, Praggnanandhaa Rameshbabu (India) 7.

Gukesh’s victory is a historic achievement. Until now, teenagers have had an indifferent record in the Candidates. Only Bobby Fischer in 1959 and Carlsen in 2006, both then 16, have been younger than Gukesh, and both were also-rans.

Garry Kasparov, who was the ­previous youngest Candidates winner at 20, called the result “an Indian earthquake in Toronto” and added “the children of Vishy Anand are on the loose” in a reference to India’s previous world champion, who mentored Gukesh and is his chess hero.

Gukesh’s career has been marked by a consistent rapid advance since 2019, when he became a grandmaster at 12 years seven months, the third youngest in history after Abhimanyu Mishra of the US and Sergey Karjakin of Russia. It was then that his family decided to support him as a professional player, despite the financial risks involved. Later, he was the youngest ever to achieve a 2750 rating, and he won the individual top board gold medal at the 2022 Olympiad. He qualified for the Candidates by finishing top of the Fide Circuit, a league table of major tournaments.

A secret of his success has been his calmness and equanimity under pressure. Away from the board, he likes to play outdoor sports, with tennis his favourite. He regularly practices yoga, which helps his stamina. He remarked that, despite his lack of experience, his youth was a strength for such a long tournament: “It’s easier to be focused at my age.”

Gukesh’s only loss at Toronto was to Alireza Firouzja in round six, when he collapsed in time pressure and his despair was captured on video . Yet from that moment his self-belief in winning the tournament grew: “I was upset, but during the rest day I felt so good that the loss gave me motivation.”

His second, the Polish grandmaster Grzegorz Gajewski, who worked with Anand for many years, said: “Anand is the brilliant one, who sees it first, but Gukesh is the calm one, who managed to keep his composure even in the most stressful moments. Apart from being a brilliant player, this is the main thing that decided the tournament.”

There was only half a point in it at the finish. Gukesh drew all six games against his principal rivals, but, critically, won with both colours against the outclassed tailender, Nijat Abasov, who dealt Nepomniachtchi’s chances a blow by drawing twice. Nakamura’s nemesis was Vidit Gujrathi, who twice crushingly defeated the popular streamer.

The 36-year-old brushed it all off two days later, when he scored a clean sweep of this week’s Titled Tuesday , opening with 1 h4 in several games. He has now won the event 71 times.

Many would argue that the World Cup, a 150-player knockout qualifying three Candidates, and the Grand Swiss, with over 100 players and qualifying two, are over-represented and should have fewer places, and that the Fide Circuit, which rewards the winners of high-class tournaments, should have more than one. Gukesh qualified from the Circuit and Caruana would have done so had he not already secured a place by another route.

The coming Ding v Gukesh match for the world crown, which will take place from 20 November to 15 December, will be the first all-Asian title match. Ding’s indifferent form in recent months means that the challenger will start favourite to break Kasparov’s record as the youngest world champion by four years, but there is a caveat.

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In an interview, Ding praised his rival: “He has a maturity that doesn’t match his age, and he has his own unique understanding of the position … He is a difficult opponent to face.” But he added: “I have the advantage in classical chess.”

Ding is referring to their only two head-to-head classical games, at Tata Steel Wijk aan Zee in 2023 and 2024, where in both cases the Chinese player trounced his opponent with the black pieces.

Months before his world title challenge, the Candidates winner has another important date – from 8 to 12 May at the Grand Chess Tour Rapid and Blitz in Warsaw, Poland, where the 10-player field includes both Gukesh and Carlsen.

China’s Tan Zhongyi won the women’s Candidates, and will now meet her compatriot Ju Wenjun for the world title. Leaders were Tan 9/14, Lei Tingjie (China), Koneru Humpy and Vaishali Rameshbabu (both India) all 7.5.

Tan, 32, and born on 29 May, the same day of the year as Gukesh, was a highly convincing winner who led from start to finish and lost only once. She revealed afterwards that she did not expect to win, as competitive chess is no longer her main priority. Instead, she has her own club and coaches talented students.

Her past achievements already include a world championship, which she won in 2017, when the event was staged as a knockout. In 2018 she lost a title match 4.5-5.5 to Ju, who has held the crown ever since, and will be the favourite in their rematch due to her good performance at Wijk aan Zee earlier this year. Tan’s best win at Toronto featured a classic king’s side attack.

The other eyecatching result in the women’s Candidates was by Vaishali Rameshbabu, sister of Praggnanandhaa, who was fifth in the open event. Vaishali lost four games in a row between rounds six to nine, then mounted an astonishing comeback by winning all her last five games. At 22, she has chances to reach the top of women’s chess, so that a brother and sister as world champions is not an impossible dream. A knight sacrifice at f7 launched a winning attack for Vaishali from a fashionable variation of the Petroff.

3917 : 1 Rxc8+ Bxc8 (if Qxc8? 2 Rxh7) 2 f7+! Resigns. If Qxf7 (Kxf7? 3 Rxh7+ or Rxf7? 3 Rh8+ Rf8 4 Rxf8 mate) 3 Qc2! with the winning double threat of 4 Qc8 mate or 4 Q or Rxh7.

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'The Veil': Release Date and Everything to Know About Hulu's New Spy Series

F rom Mad Men to The Handmaid's Tale , Elisabeth Moss' work has seen the Emmy-winning actress take on complex characters who overcome incredible odds. In The Veil -- FX's upcoming six-episode limited series from Peaky Blinders creator Steven Knight -- Moss plays Imogen Stalter, a brilliant MI6 agent tasked with thwarting a terrorist attack by bringing a suspected terrorist to justice. 

Knight wrote all six episodes. Denise Di Novi, Knight, Moss and Lindsey McManus executive-produced the series. 

See at Hulu

During the 2024 Television Critics Association winter press tour, Moss joined Knight, Di Novi and cast members in a panel presenting the series to select press members. CNET attended the panel and chatted with Moss and Di Novi to get further insight into FX's globe-trotting spy thriller.

Read more : What to Watch in 2024: 50 TV Shows We're Excited About

When to watch The Veil on Hulu

The first two episodes of The Veil will premiere on Tuesday, April 30 exclusively on Hulu. The remaining four episodes will debut every Tuesday on the streamer. These are the episode titles:

• Crossing the Bridge
• Declassified
• Grandfather's House
• The Cottage

For audiences residing outside of the US, the show will eventually be streamable on Disney Plus in the UK and other countries. For Latin American viewers, the show will come to Star Plus. The premiere date for both platforms has yet to be announced. 

What is The Veil about?

According to the official synopsis, "FX's The Veil explores the surprising and fraught relationship between two women who play a deadly game of truth and lies on the road from Istanbul to Paris and London. One woman has a secret, the other a mission to reveal it before thousands of lives are lost. In the shadows, mission controllers at the CIA and French DGSE must put differences aside and work together to avert potential disaster."

Most of the show takes place on the run. It's during these moments that secrets are revealed, and perceptions of the truth get twisted. It all unravels in a multitude of layers until the very last scene.

"Thematically, a lot of what the show is about is what is true and what is not true?" Di Novi told CNET. "Obscuring the truth ... what does that do to people? For our characters, there's connection, but there's always this kind of veil of not quite being who you really are and not quite saying exactly what you want or what the truth is."

"There's something about this woman that Imogen sees, and she can't quite put her finger on it," Moss added. "They're both like, 'I know this woman, I know this person, there's something there.' Is it something good? Or is it something bad?"

Every player on this proverbial chess board has an agenda and something to conceal. Imogen's job is to hide in different identities, making the story quite complex. Knight wanted to portray these characters as neither heroes nor villains, a trope that would diminish the show's point.

"The idea that you would treat one of the human beings as not being a human being would be very reductive and wouldn't be a very interesting drama," he said. "There's no attempt or wish to present the known thing from the other. I think if you watch and you understand the character that Yumna plays, then there is something very familiar and very us about all of this. There isn't any need, I don't think, to create that division."

Who stars in The Veil?

Accompanying Moss in FX's new limited series are Yumna Marwan as Adilah El Idrissi, Dali Benssalah as DGSE agent Malik Amar, Josh Charles as CIA agent Max Peterson, James Purefoy as Michael Althorp, Alec Secareanu as Emir and Thibault de Montalembert as DGSE agent Magritte. 

"By design, this was an international show," Di Novi explained during the TCA panel. "Very early on, because of the agencies we're working with, Steve and I talked about our desire and love to shoot in Paris and England -- where Steve is from -- and Turkey. We had a design that came out of the characters for those locations. We made a commitment from the get-go to show these places in ways you had not seen before and show Paris in a way that was not your kind of touristic, romantic vision of Paris." 

Understandably, the series' international scope is reflected by its diverse cast. Moss told CNET, "We literally have like one American on our show. That's it." (Moss is half-British and holds dual citizenship in the UK and America. Charles is the American she's referring to.)

Is The Veil based on a true story?

Di Novi had the idea that inspired The Veil. According to Knight, she suggested "there was friction between the various intelligence agencies, MI6, DGSE and CIA." How does dealing with global threats impacting the three agencies affect the greater good? Knight called it "a very fertile area."

Bits of authenticity bound The Veil together. The six-episode series features plenty of conflict between the intelligence agencies. Knight did some sturdy research to represent these security apparatuses properly. 

"I went to Paris," he explained. "I met three people who worked in French intelligence. Two of them were DGSE, two of them were non-attributable. I just asked them, 'What's going on? What are the stories?' Because I always find that the true stories are much more compelling."

He continued: "The thing that appeals to me most is when big, big, big international conflicts and events boil down to individuals. What I wanted to do with this was to take huge issues and boil it down to two people in a car driving through the snow, and the nature of the conversation affects the outcome for thousands of people."

The Veil challenged Elisabeth Moss more than The Handmaid's Tale

Moss, known for her portrayal of complex characters, faced a new set of challenges with Imogen. One of the most noticeable is her British accent, a result of months of dedicated work with a dialect coach. This commitment also extended to the fight choreography, where Moss, for the first time, took an offensive stance, practicing relentlessly for weeks on end. 

"I've done some fight stuff before in Handmaid's Tale and Invisible Man," she added. "But it was very defensive. It was never offensive. I'm always the person who's being attacked and having to defend myself. This was the first time I've played somebody who had training to kick the shit out of people. I had to look like I knew what I was doing." 

Moss, a master of transformation in her acting career, saw a reflection of this in her role as the MI6 agent. Imogen, she believes, is not just a shapeshifter but also an actor, a unique and intriguing combination.

"The first conversation I ever had with Steve was about this shapeshifting concept," Moss said. "He was talking to me about a woman who is really, really good at playing other people and can just put on a different person and take them off. She's really good at it and really enjoys it; it isn't a negative thing for her. He went on and on, in his beautiful way. At the end of it, I was like, 'OK, so she's an actor?' And he was like, 'Yes, exactly.'"

During the TCA panel, she tallied up all the challenges she faced in the series and came to a baffling conclusion: "I had found something even more challenging than Handmaid's [Tale], which is impossible to say."

Will The Veil return for more seasons?

Imogen is an MI6 agent who makes a living becoming other people. Knight wrote this series from the outset with the potential for more seasons in mind.

"On the point of how far can this go, how many different incarnations can there be," he told the TCA press members, "one of the things that informed the character when I was writing it was that I knew someone -- this is a true story -- who told me, who was British, that he had a grandmother, and she was 65, and she was retiring. She called everyone to the house for Sunday lunch. Over lunch, she said, for the past 35 years, I've been an MI6 agent." 

He continued: "No one knew that was what she did. That's a true story. If someone can live that as a life, actually as a life, that's what I think is interesting."

Could Imogen Stalter be FX's answer to Jack Bauer? After all, both characters work for their respective governments and have no qualms about going rogue or coloring outside the lines to keep people safe. While the future of the series is still unknown, there's promise for more adventures. 

"I felt that we just scratched the surface of who she could be in such an exciting way," Moss said.