Danny and Jackie investigate the suspicious death of Phil Gibson, a high-rolling investor who sustained injuries in a fight, although his hands appear unmarked by trauma. After receiving an anonymous tip to investigate a nightclub, Danny learns that the investor was involved in a secret "fight club" boxing ring put on by Wall Street bankers. They learn that Gibson's fight was part of an initiation process for all young employees with their bosses betting on the matches. Danny proves that Gibson's boss is responsible, having doctored the gloves of his opponent in order to guarantee Gibson would lose his fight. Meanwhile, Frank forces Jamie under house arrest when the Sanfinos put out a hit on "Jimmy Riordan," Jamie's undercover identity, as well as Noble Sanfino. Wanting to warn Noble of the danger he's in, Jamie confronts him with his true identity and offers him a plea bargain to testify against his family. He reluctantly agrees and Noble and his sister More...go into witness protection.