Simone and Sipowicz investigate the murder of a nurse where the suspects include a struggling actor, a crazy man, and eventually a uniformed officer from the precinct named Tommy Richardson. Meanwhile, Medavoy and Kirkendall look into the death of a bicycle messenger who was killed for just trying to help a man whose backpack was stolen, so they determine that the backpack contained drugs. When they get a suspect into custody, Kirkendall figures out a clever way to get an ID on the suspect who won't cooperate. Also, Sipowicz's doctor tries to talk to him about how to deal with his medical problem, but Sipowicz won't listen.

Richardson confronts Sipowicz and Simone about their impending questioning of his wife over the murder of the nurse, but with the exception that Richardson is a real bad person, Sipowicz and Simone reach nothing. In a cross-over from the series "Upstairs", former temp and private detective John Irvin stops by the station to tell the detectives about the new graphics art business he started. But with the exception of the receptionist Dolores, no one is around, including Medavoy who leaves in a hurry for upstate New York where Abby now lives to be by her side when she goes into labor. Meanwhile, Kirkendall and Russell look into the theft of a graduate film student's camera, where only the student seems more interested in dispensing his own justice. Also, Sylvia finally learns about Sipowicz's medical condition from his doctor and finally persuades him to go for further tests and possible surgery.

The detectives get a break in a case involving a police officer suspected of committing murder.