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.