Officer Lewis Powell fell off the wagon and woke up in an alley covered in blood with his off duty weapon missing. He tells Walsh he may have killed someone the night before during an alcohol-induced blackout and asks for his help. While Walsh and Shraeger scramble to put together the pieces of Lewis' missing night, Banks and Delahoy learn they are both victims of identity theft. When they investigate the murder of the man pretending to be Banks, Delahoy and Banks get a glimpse into the lives of the men who've stolen their identities and consider changing the way they live.

While Sergeant Brown is away, Alvarez is in charge, and things aren't going well. A U.S. Marshall named Foster convinces Alvarez to release Bo Keebler, a man recently collared for trying to rob a Chinese restaurant, into his custody. But after a fake bomb threat is called in to the precinct, Casey, Alvarez and Walsh discover that Foster is not all that that he seems. Meanwhile, Banks decides to stay in his apartment until he turns 43 in order to avoid getting killed.