Boxers Henry “Razor” Sharp (Sylvester Stallone) and Billy “The Kid” McDonnen (Robert De Niro) become rivals after two fights, one in which Kid beats Razor and one in which Razor beats Kid. Before they have a rematch, Razor announces his retirement, ruining both of their careers. Years later, Razor is working in a shipyard when he’s visited by promoter Dante Slate Jr. (Kevin Hart), who wants Razor to provide a motion capture performance for a video game. Razor begrudingly accepts $15,000 needed to renovate his house. At the recording studio, he is surprised by Kid, who was also invited by Slate, and the two get into a fight and damage the studio’s equipment before being arrested. Cellphone footage of the fight is uploaded on YouTube and goes viral, giving Slate the idea of organizing a final fight between Razor and Kid, which he calls a “Grudge Match”.