Dietrich volunteers for a stress analysis study on police officers, and as a result causes Barney and his colleagues concern when the harness he's wearing stops working when he goes on an assault case. Harris and Wojo go on a call to NYU, where a Peace Corps recruiter causes a disturbance at job fair. Meanwhile, Inspector Luger stops by to express his displeasure in the letter Barney wrote for him to send his mail order bride.

It's Christmas and the detectives room soon gets overrun with vagrants with nowhere to go. Wojo and Dietrich bring in a homeless suspect and a merchant who caught him sleeping in his business and ultimately assaulted him with a cattle prod. Harris brings in a suspect who caused a disturbance when he was fired at his office Christmas party.