Peter Coventry Smith

Olinsky's daughter remains in critical condition following a massive fire - leaving Intelligence on edge, but more determined than ever to track down the suspect. Voight opens up the case, knowing that he has Stone and his team's full support in the investigation, and all of Firehouse 51 behind him to examine potential origins of the fire. Intelligence works to connect the dots between the building owner, those who were inside, and a string of potential suspects.

Former international CIA operative Wesley Cole returns home and becomes Murtaugh's partner on the force; Avery continues his campaign for city council.

After an apparent threat is made on Riggs’s life, the squad is on high alert, but with Murtaugh taking on more responsibility at work, he and Riggs have to deal with their changing relationship. Meanwhile, Trish gets caught up in some trouble, and Molly asks Riggs to make a decision about their future in the second season finale.

On Murtaugh’s first day on the job as interim captain, the wife of a popular businessman is abducted, and the squad finds a connection in the case to Riggs’s father, Nathan Riggs (recurring guest star REX LINN). Meanwhile, Riggs is left to grapple with his family and work.