Liar Game is a Japanese manga series originally written and illustrated by Shinobu Kaitani. The manga was first serialized in 2005 in the Japanese manga magazine Weekly Young Jump, published by Shueisha. It was later adapted into a drama series, which started airing on April 14, 2007 on Fuji TV, achieving a 11.4 viewership rating in the Kantō region.
Nao Kanzaki, an honest college student, receives 100 million yen (about $1,000,000) one day, along with a card saying that she has been chosen to participate in the "Liar Game Tournament". In order to win the game, she is to steal the 100 million yen issued to her sole opponent, and to keep hers safe. Upon finding out to her opponent is her former teacher Kazuo Fujisawa, she misplaces her trust in him and is easily deceived. Knowing that losing the game will put her in debt, a lawyer tells her of Shinichi Akiyama, a genius swindler.
Akiyama had just finished a prison term for driving a multi-level marketing corporation into bankruptcy, and at first refuses to help Nao. After seeing her trusting nature, he decides to help on the condition that he receives half her profits. Though she is left in the dark about his plans, in the end he steals not only Nao's 100 million yen back but Fujisawa's as well. After returning the 100 million yen she was first issued by the LGT, Nao has an extra 100 million, while her teacher is in debt. Though she gives 50 million to Akiyama as promised, she gives her own share to Fujisawa so that he can reduce his debt. Seeing this, Akiyama also returns his share. He claims that as he promised to get only half of what Nao earns; if she receives nothing, he receives nothing too.
Then Nao receives another card, inviting her to continue to the second round of the Liar Game. If she wishes to drop out, she must pay 100 million yen. Since Nao gave that money to Fujisawa to pay off his debt, she knows it is impossible. The same lawyer she had consulted with encourages her to go to the address of the game and tell the mysterious organization to leave her alone, and she takes the advice. It doesn't work, and forced to play she arrives to the mansion where all the other first round 'winners' are. Just as the game host, Leonira, starts the game Akiyama enters as one of the players. He had tracked her down and takes the spot of a player who didn't wish to participate. Thanks to team strategy Akiyama develops, he wins the game and divides the prize money among their team. However, after paying off everyone's debts Akiyama doesn't have enough to drop out himself. He reassures Nao that it doesn't matter because he's interested in continuing the game and finding out who is behind it. After this, he loses contact with Nao.
Guilt driven, Nao enters the Liar Game Revival Round, meant for those who lost the previous round of the Liar Game. She intends to win in order to get the money necessary to pay the cost for Akiyama to drop out. Unfortunately, she is tricked by one of her opponents, Yuuji Fukunaga, as she had been in the Second Round. Again, Akiyama arrives to help her and under his guidance she tricks everyone into giving her the needed votes to survive the game. Not only does she win, but she helps the only person who had been kind to her, Miura Takayoshi, pay the drop-out fee.
Soon the third round begins. Akiyama, Nao and the other winners of the Revival Round are sent to an abandoned airport building, the location of the game. The game is a "contraband game", a team game in which each team must smuggle money out of an opposing country so it can be transferred to a third country. The two main countries in this game are labelled "Northern Country" and "Southern Country", and are represented by two adjacent rooms. All the players of the Revival Round are the Southern Country; for the first time they are working together against the Northern Country.
One member of the Northern Country, Norihiko Yokoya, seems to be clairvoyant, declaring the exact amount of money smuggled each time he is the customs official, no matter how odd an amount is smuggled. Meanwhile Takahiro Kikuzawa, a member of the Southern Country, figures out a way to determine if the smuggler is carrying any money, which allows him to stop the Northern Country's smuggling attempts every time. Kikuzawa uses this to become leader of the Southern Country and dominate the other members. However he slips up, and Akiyama figures out that Yokoya and Kikuzawa are allied, telling each other how much money their team was smuggling each round. Nao convinces the Southern Country to forgive Kikuzawa because otherwise the team would fall apart and they would lose.
Soon Akiyama comes up with a plan to win the game: genuine smuggling. The Southern Team will get someone on the Northern Team to ally with them. That traitor would transfer all the Southern Country's money into his own account. At the end of the game the Southern Country would have gotten less money from smuggling than the Northern Country, and thus would lose and drop out of the Liar Game. However, when each team's unsmuggled money would be transferred to the opposing team, the Southern Country would have more money. Thus with this plan, the Southern Country would not only win a lot of money, but also automatically be dropped out from the Liar Game. However, before Akiyama had revealed his plan the Northern Country had tricked three members of the Southern Country into transferring all of the Northern Country's money into the Southern's Country's account. After the confession of the three members (Eda,Tsunoda and Kitamura), Akiyama revealed that he had already found a way to increase their winning chances.
When the member of the Northern Country who tricked Eda, Kouta Akagi, comes into the inspection room, Akiyama faces him and tells him that the Northern Country had made a mistake: they don't know whether Eda and the others really paid all the money into the North's ATM. The Southern Country has hidden the money so that the Northern Country can't lay a finger on it; according to Akiyama's revelation, the Northern Country has no chance of winning. Obviously it is a bluff, but it seems to work on the smuggler, who was panics and prays Akiyama to save him. Kouta reveals the story of how Yokoya came to dominate them: in their Revival Round, Yokoya substituted for another player, so it was his first round in the Liar Game. The 8 other players had agreed to give each other their votes to ensure Yokoya would lose. However for the first two rounds Yokoya had bribed everyone's votes and gotten all 80 of them. He then sold his extra 29 votes to get everyone else's money. This put everyone in a 200 million debt to Yokoya, except to the person who was most loyal to Yokoya, whom Yokoya let drop out of the Liar Game. Akiyama then tells Kouta how their Revival Round followed a similar course, except the person who won returned all the money; this convinces Kouta to join the Southern Country. Akiyama then convinces Yusuke Shibayama from the Northern Country to join the Southern Country.
Kouta also elaborates on the specifics of Yokoya's control system. Yokoya has set up a "Loyalty System". For successful smuggling and obeying Yokoya one gains Loyalty points, and one loses them for the opposite. Yokoya also rewards his teammates for spying on each other and exposing disloyalties. At the end of the game, Yokoya will give money to the six people with the most points (and enough to clear their 200 million debt to the top 3). This isolates the players from each other, and consolidates Yokoya's control. Fukunaga realizes that Yokoya isn't actually keeping track of points; he's probably telling everyone they're around fourth place, so that they are eager to get points to rise to the top, but careful not to disobey him and fall too low.
Meanwhile, Yokoya realizes that the Southern Country is up to something because they are purposely losing a lot of money. Right when the outside account balance of the two countries is about to become equal, the Northern Country calls doubt on 99 million, 990 thousand, giving the Southern Country about 1.5 mil. When a member of the Northern Country spies on Yusuke and Kouta, discovers they're traitors, and reports this to Yokoya, Yokoya orders Kouta and Yusuke to be tied up and blindfolded. Yokoya then plays the "Confession Game" with them. He tells them to confess that they are traitors, and that he will not punish them in any way for it. The first person to confess will be ensured that he will be at the top of the Loyalty Chart and will receive a bonus of 200 million, but the second one to confess will lose enough loyalty points to automatically be last in terms of Loyalty Points. However, if neither confesses within ten minutes, he will assume neither are traitors and let them go. Kouta lasts the entire 10 minutes, while Yusuke hears a strange noise and, thinking Kouta has done so, confesses in the first minute. Akiyama enlists the "help" of a third Northern Country member, confirming the Southern Country's plan. Yokoya promises Kouta that he will receive no penalty as long as he plays his role in Yokoya's new plan well.
Informations source: Wikipedia