Nikiya Mathis

While awaiting his arraignment, Naz realizes that his survival rests in the hands of an inmate.

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.

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.

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 as a dispatcher in an emergency call center to protect a 911 operator who's being forced to cooperate with the kidnapper of a young boy.

After nearly six months of dating, Marcus and Mia are ready to take the next step. But when she returns home and reconnects with her long-estranged father, Mia experiences complicated feelings that put her relationship in jeopardy.