Billy Smith

Erin is overwhelmed with guilt after a man she set free is accused of killing a cop. Also, Frank and Mayor Poole continue their game of political chicken over Frank's reappointment as commissioner, and Danny and Maria investigate a case of a cop who has gone AWOL.

Emotions run high when Eric Matheson, accused of murdering his wife, takes the Lightman Group hostage to force them to help him uncover the real murderer.

A woman asks the NCIS team to investigate the death of her husband, a Marine who specialized in K-9 bomb detection; Vance interviews nannies.

The murder of a rare bookseller brings Jane and Maura into the world of Keltic writings and coded confessions, just as Maura is preparing Jane to meet her new man. Angela's relationship with Cavanaugh changes pace.

Tommy Caffee's brother returns from being on the lam; Tommy's wife, Eileen, deals with her demons via drugs and alcohol.

Brody's efforts to sever ties with Abu Nazir triggers flashbacks to his time as a captive. Meanwhile, the mosque shooting results in a public-relations nightmare for Carrie.