Elena, Jack's ex-girlfriend, is found dead in an alley, shot three times. The prime suspect is a Latvian businessman who she had often been seen with in a coffee bar.

Santoro is asked to help out his nephew with a few speeding tickets and ends up losing his temper with the highway cops and insulting them.

Doyle and Ray keep being called to the apartment of a couple who are continuously fighting.

Ann-Marie starts her first day as a detective and begins by organizing a raid on an apartment where an informant has told her two men are making bombs.

The precinct gets a new PAA, someone Phil remembers from his old precinct. He tells Santoro that she has a obsessive compulsive disorder that involves cleanliness and having to do everything four times. She is so annoying that she is always getting moved from station house to station house.

An arrested drug dealer dies in a cell in the station house. The coroner determines that he died from strangulation, which puts Doyle in a jam as he was the arresting officer and was supposed to have kept an eye on his prisoner.

Clem is approached outside a supermarket by a man who has a plan to scam the business' owners. A sting is set up to arrest the man but things do not go according to plan.