In New York City, a young counterfeiter is introduced to the world of underground street fighting by a seasoned scam artist, who becomes his manager on the bare-knuckling brawling circuit.
Shawn MacArthur, the kind-hearted son of an Alabama wrestling coach, makes a grim living selling fake products on the streets of New York City. After dealing with thieving punks, he's discovered by bare-knuckle/street-fight manager Harvey Boarden. Shawn soon proves himself worthy and starts earning a small fortune, part of which he volunteers to spend on single mother Zulay Velez. Shawn doesn't cheat and that seems to be a major problem, notably after the arrival of his Alabama high-school rival.
- Present day New York City: Shawn MacArthur (Channing Tatum) is a street hawker. One day while selling counterfeit goods at the corner of Radio City Music Hall, a group of young men attempt to force Shawn to relocate with his merchandise. These boys work for Harvey Boarden (Terrence Howard), a ticket scalper who controls the corner. Shawn fights them off, but does not retain his money or products.
Later, Shawn sees Harvey and the guys who stole his money in a cafe and confronts them. Shawn takes back his money back, but Harvey offers him a chance at a "winner takes all" fight for money. Harvey sets up a meeting with his friend and rival, Martinez (Luis Guzmán). Shawn's first fight is at a Brooklyn church against a Russian. He wins when he knocks the Russian into a water fountain. Harvey takes Shawn to a club where he meets a waitress named Zulay (Zulay Henao), a single mother to whom Shawn had earlier tried to sell a fake Chinese Harry Potter book. In the VIP area to the club, Shawn also meets Evan Hailey (Brian White), a professional fighter who used to be on the same college wrestling team as Shawn and was coached by Shawn's father. Shawn and Harvey leave after Evan and Shawn nearly get into a fight. Shawn's second fight is at the back of a store in the Bronx, against a much larger opponent. The fight descends into chaos after some of Harvey's crew interfere when the opponent nearly chokes Shawn, and the woman who owns the store pulls out a gun and shoots when one of the guys spills her drink. Harvey, Shawn, and the rest of Harvey's crew flee the scene and neither fighter gets paid. Shawn's third fight is at a penthouse in which Shawn is victorious against a martial arts fighter. Later in the day, he goes to a club to celebrate, Evan is there and instigates a confrontation with Shawn, taunting him on his current status and his father.
Between fights, Shawn continues to court and romance Zulay and they eventually have sex. Zulay later asks Shawn on the subject of his family, in which he reveals that the reason why he and Evan have such a bitter rivalry is because Shawn's father coached the wrestling team that he and Evan were in. Shawn's father showed more affection toward Evan while Shawn was consistently bullied by other teammates, including Evan. Having had enough, he lashed out at Evan, and when Shawn's father tried to break them up, Shawn, in a blind fury, beat his father to a pulp and, understandably, hasn't seen or heard from him since the incident and knows he will probably never be forgiven. Shawn and Zulay are later visited by Harvey, and Shawn, suspecting Zulay and Harvey of having sexual relations, is furious. Harvey explains that Zulay places bets for him discreetly.
Shawn and Harvey are offered a fight against Evan, and Shawn accepts, but Harvey wants him to throw the fight so that Martinez and his associates can make money. Shawn agrees to throw the fight. Zulay places the bets, a total of $500,000. Shawn and Evan fight, with Zulay, Harvey, and the rest of the crew watching. Evan has Shawn in a chokehold and it appears that Shawn is about to throw the fight; however, he fights back and overpowers Evan. Shawn wins, and Martinez threatens Harvey. At Harvey's apartment, Shawn reveals that Zulay reversed the bets and they have one million dollars. Zulay picks up Shawn and Harvey, and they leave New York with Zulay's daughter and grandmother.