Still grieving the loss of her husband and the failed relationship with Danny Sorenson, Diane Russell decides to take the drastic step of leaving her job in order to get her life back together. But the manner in which she leaves has her co-workers, particularly Sorenson, feeling hurt and confused. Meanwhile Medavoy and Sipowicz go undercover to nab a pair of robbers who've been preying on the elderly, while Andy wonders openly whether his plans to marry his ex-wife are a good idea. Danny meets a stripper while working a double-murder case and seems to be falling for her.

Everyone in the department fears the worst as Sorenson is missing and Kristen, the stripper he dated, is found dead in his apartment. As the detectives all desperately cling to the belief that he is not the murderer, concern and fear for their colleague cloud their search. Lt. Rodriguez gets the squad to focus on the job and helps them close a murder case involving a gay hustler and a Reverend's wife.