Nash and Joe follow the trail of a criminally insane mental patient who believes he is the nemesis of Sherlock Holmes. Joe hires a baby nurse who takes over his life.

A million dollar bounty on Nash's head triggers an onslaught of attacks by a series of ultimate fighters. Michelle meets ""Mr. Right"" while on a stake out trying to trackdown an Internet rapist. Nash is convinced Cassidy's new boyfriend in gay.

Nash is out of action after Caitlin accidentally shoots him in the butt. Joe and Bettina do a joint investigation with FBI agents to bust a clever con-artist. Cassidy is stalked by a deranged college student.

Nash and company foil a jewelry heist ring posing as firemen. Nash hits a pedestrian and gets sued. But Caitlin has misplaced Nash's auto insurance bill, and he blames Caitlin.

A nurse who assists a plastic surgeon for the mob is murdered because she stole the before and after photos of altered mobsters. She passes a key to the hidden files to Joe, and Joe becomes a target of mobster Louis Fallon. Nick appears with Cassidy in her play, but suffers a bout of Alzheimer's. Harvey meets a new girl, but she is a former lesbian.