The Devil's Plan

The Devil's Plan (데블스 플랜) is a South Korean reality game show. The first season premiered on September 26, 2023, on Netflix. Twelve contestants compete in both collaborative and competitive strategy games in order to win a cash prize.

Format
Twelve celebrity contestants are initially given one "Piece". A player with no Pieces is eliminated; Pieces can be traded between players or spent on in-game benefits. Pieces can be won and lost in the two daily matches: the Main Match and the Prize Match.

After the competitive Main Match, the two surviving players with the fewest Pieces are sent to prison until the next Main Match. The player or players with the most Pieces make tie-breaking decisions about who is sent to prison. The collaborative Prize Match determines whether a sum of money—₩50,000,000 or ₩100,000,000—is added to the final pot, which can total up to ₩500,000,000.

Games featured include social deduction games, board games, card games and abstract strategy games like nine men's morris. Main Matches typically see players forming alliances, while the Prize Matches test skills including memorization, numerical calculation and visualization.

Combining three different types of pieces forms an octahedron-like shape from which the clue "NEXT YEAR" can be read. Using this clue—by typing 2024 into a hidden safe in the prison—unlocks a special individual challenge - a variant of Gomoku in which the player must remember the colour of each piece, in which the player can win 10 Pieces but risk elimination from the game.

Gameplay
Besides the first main match, players ending with a total piece count lower than one were eliminated.

Day 1 Main Match: The Virus Game
Players randomly selected a number dictating the order they would select a card from twelve laid out inside the dealer room. Each card had a role on it which the player would be. The roles were:


 * Terrorist (tries to kill all citizens). Each terrorist has one bullet, which they can use to kill one player. Each terrorist also has one virus, which they can infect one player, and the virus spreads through the number order. Players infected with the virus after one round are killed. There are two terrorists.
 * Fanatic (tries to get killed by the terrorists or virus). Unlike popular social deduction games such as Among Us, there is no voting to eliminate players. Depending on how early the fanatic gets killed, they receive varying amounts of pieces, with a higher count the earlier they die. There is only one fanatic.
 * Officer (tries to kill the terrorists). The officer gets one bullet each round, and gets varying amounts of pieces depending on how successful they are. There is only one officer.
 * Ordinary Citizen (tries to eliminate the terrorists) is unable to do very much besides observe, as they have no special abilities. One of the ordinary citizens contains an antidote to the virus, without their knowing, that grants them immunity from the virus. There are five ordinary citizens.
 * Researcher (tries to develop antidote using the citizen with the antidote). The researchers do not know who carries it, and may choose one person each round. If they are successful, the development process continues for the cure. If they succeed, the citizens win the game. There are two researchers.
 * Journalist (tries to eliminate the terrorists). The journalist can investigate one player each round, and discover their identity. They can then relay the information to the officer (whose identity is hidden), who can then kill one of the terrorists. There is one journalist.

In the turnout of the round, the terrorists won (Guillame Patry and Lee Si-Won), with Lee Si-Won having been killed by the officer (Ha Seok-Jin). The fanatic (Kim Dong-Jae) died of the virus, and earned one piece. The researchers (Seo Dong-Joo and Boo Seung-Kwan) failed to create the cure. The terrorists received four pieces each, and the fanatic received one piece.

Day 1 Prize Match: Cooperative Puzzle
After every main match came a prize match where, if the players won, either ₩50,000,000 or ₩100,000,000 would be added to the prize pot. For the first prize match, players stood on a roundabout that would spin around for three minutes, with twelve sectors on it, with one player standing in each. Each player was in front of the puzzle for five seconds, with the roundabout making three rotations. The puzzles showed an empty geometrical shape, and were given pieces outside of the puzzle, that they had to put in the puzzle correctly. If the players completed all ten rounds, then a certain amount of won was added to the prize pot. If a player solved the puzzle twice, then they received one piece for every next puzzle solved. The prize match failed.

Day 2 Main Match: Rules Race
For the second match, players were required to create specific personal rules only applying to themselves for a board game following certain criteria. The players went in an order based on the amount of characters each player's rule had. Players rolled a die with sides depicting one, one, two, three, prison and escape prison. There are four offices scattered throughout, and if a player lands on one, they can gain an escape prison card, roll again, or change the group rule, which applies to everyone. There is also a 'special die' which has sides one, two, two, three, three, and three, but is only used when a special rule is activated. If a player lands in an office due to a group rule, they receive no benefits. The first player to cross the finish line receives three pieces, second two, and third one. The tenth person to cross the finish line has to return one piece, eleventh three, and twelfth five.

Day 2 Prize Match: Fragments of Memory
For the second prize match, players were tasked to observe a hospital scene, of which they would answer questions about. For the questions, (10 in total) the players went into the Dealer Room, where they would wait while one player answered questions. The player answering could either:

1) Pass, which resulted in the player leaving the main area, and another player would come in, or

2) Answer, which, if correct, would let them answer another question. If the question is answered incorrect, the prize match would end in failure. Players needed to answer all ten questions correct to win the prize money. The prize match ended in success.

Day 3 Main Match: Secret Number
For the third main match, players each have a secret number between 1 and 100. Players gain clues about their own and others' secret numbers by joining another player private room and submitting a ticket to gain information about the combination of their numbers. Points are awarded based on players accurately guessing each players' secret numbers, including their own, and for keeping their own number secret.

Day 3 Prize Match: Word Tower
For the third prize match, the group of players is given a tower of wooden letter blocks and a category. They must use the blocks to assemble as many English words in the category as there are players, while using up all blocks. The prize match ended in success.

Day 4 Main Match: Zoo
In the fourth main match, players seek to fill a 5x5 grid with a pattern of animal tiles that suit their personal winning condition. Each player has a secret sequence of three animals out of five possible, as well as a condition card specifying that one animal will appear in the grid more times than another animal (ex: more lions than monkeys). Players are then given a limited set of chips to bid during auctions that allow them to place tiles on the grid.

Day 4 Prize Match: Scale Game
In the fourth prize match, players are separated into groups of two to three and placed in separate rooms. They must jointly determine the mass of five differently colored blocks that each weigh between 1g and 20g. In turn, each room may add cubes to virtual scales. All rooms will see whether the actions result in the scale tilting one way, the other, or being balanced. When the scale is balanced, players have an opportunity to guess the five weights. One value is given to start.

Day 5 Main Match: Laying Grass
The fifth main match is played on a 30x30 grid. Players play take turns selecting polyominos to add to their territory. Each piece must touch one of their existing pieces and may not touch any other player's territory. Players who surround key squares gain beneficial actions such as the ability to steal from or block another player. Pieces are awarded or deducted according to the largest complete square within the player's territory.

Day 5 Prize Match: Montage
In the fifth prize match, players watch a slideshow of portrait photos. Each shows for 3 seconds. As soon as a duplicate photo is shown, at least one player must buzz in. The group has a limited number of erroneous buzzes allowed before the prize match ends in failure.

Day 6 Main Match: Equation High-Low
Players use number and mathematical operator cards to form equations. They bid on whether they can form a result closest to 20 or closest to 1. All players' pieces are converted to chips before the game starts, and players are eliminated when they run out of chips until three players remain.

Day 6 Prize Match: Four Player Three in a Row
Players are separated into individual rooms to play a three-in-a-row game against each other and an unknown fourth player. In each game, the colors are assigned based on a set procedure not shared with the players. Players succeed when the prevent the unknown fourth player from winning. The two players with the most pieces at the end of the match proceed to the final.

Final Match
The final match comprises three 1:1 games. Whichever player is the first to win two games becomes the winner of Devil's plan.

Secret Chamber
The Secret Chamber had a safe in prison, with a 4 Number code, Ha Seok-jin the person who had cracked the code, got a clue "Next Year", So the code was 2024. The secret chamber game is blind gomoku, where tiles are one-sided and placed face down, so that the player must memorize which tiles are theirs and which are the opponent's. Lee Si-won gave a first attempt but failed, and lost all of her pieces and got eliminated in Night 5, In the morning, after Night 5, Ha Seok-jin had a attempt and won the game and got 11 more pieces.

Contestants
Most of the contestants are singers, actors or entertainers.

Production
The program was produced by Jung Jong-yeon, who has worked in the survival reality show genre before, such as on The Genius. He said that adjustments were made as the show progressed because the contestants' behavior was unpredictable. Runner-up ORBIT, who lacked competitiveness, played with an unusual strategy by collaborating to save players from elimination. Jeong said that it was not the direction he wanted the games to progress in but that it created a new narrative for the genre. The first season concluded with Ha Seok-jin winning ₩250,000,000.

In November 2023, Netflix renewed the series for a second season.