When Wojo brings in a suspect for breaking into a warehouse he soon collapses. Once a doctor gets called up to the squad room to diagnose the suspect, everyone is ordered to stay under quarantine until tests determine if he has chicken pox or smallpox. Meanwhile, Marty and his partner Darryl turn to Barney for help in getting a character reference in order to be able to move to San Francisco, and Fish books a prostitue.

The squad investigates a hijacked bus that crashes in the neighborhood.