22 year old Melissa finds her dock-working father's work place injury fishy. Her subsequent murder has the mob's M.O. But, an injured Doyle, the mobster and Isles' father, claims innocence. Rizzoli frowns on Isles' chess game with Tom.

Jane and Maura investigate the murder of an army veteran, 29 year-old Bernard Avery, who was killed in an alleyway with a hatchet. He was homeless, one of many ex-servicemen now living on the streets of Boston, and suffered from PTSD. When Rizzoli and Korsak visit a psychology center where Avery had sought help, Jane is surprised to find her old friend Casey Jones working there. He's been back for several months but refuses to tell her anything more. The police soon have a second dead homeless vet and Jane's informant, Rondo, thinks he's found a witness. Meanwhile, Maura meets Dennis Rochmond and after saving his life, he sends her orchids. She also discovers her wild side.