Caught in an unfortunate case of mistaken identity, a man named Slevin Kelevra finds himself in the middle of a war between two rival New York City crime bosses, known as The Boss and The Rabbi. After losing his wallet, Slevin is mistaken for his friend Nick Fisher, who owes gambling debts to both mobsters. As Slevin navigates this dangerous world, he is watched by a relentless detective named Brikowski and a mysterious assassin called Mr. Goodkat. With no easy way to prove his identity, Slevin must concoct a plan to survive.

As the stakes rise, Slevin is forced into an elaborate scheme by The Boss, who wants to use him to settle a personal score with The Rabbi. Unbeknownst to the crime lords, Slevin has his own hidden agenda, as his past connects him to the present situation more than anyone realizes. He must use his wit and cunning to turn the tables on The Boss and The Rabbi, seeking to outmaneuver them in a deadly game of strategy and revenge, all while the walls close in and his list of allies dwindles.