Nikiya Mathis

Sherlock tries to catch Martin Ennis, an erratic criminal, before he strikes again; Sherlock works with an FBI profiler who wrote a book on Ennis; Watson may be evicted from her apartment.

Elizabeth makes a secret trip to Iran in hope of preventing a coup that could affect President Dalton's administration; Elizabeth's staff is brought up to speed on the investigation into Marsh's death.

Finch goes undercover in an emergency call center to protect a 911 operator in a state of emergency, but it soon becomes clear that the threat reaches further than the team could have anticipated.

When an inmate comes in with an entirely preventable illness, Max, Sharpe and Iggy head directly to the source -- Rikers Island; Bloom struggles with her recovery; Reynolds gets news that could change his life.

When Danny accepts a side job as a bodyguard for a recently released ex-con who took the fall for someone else, he uses the opportunity to go after the real criminal. Also, Gormley's wife asks Frank to give him a bigger command position.

As he awaits his formal arraignment at Rikers Island, Naz realizes that his survival, or perhaps his demise, rests in the hands of a particular inmate.