In the fifth season premiere, Officer Cooper clashes with his new "boot" - Gary Steele (DEREK RAY), while Lydia Adams tries to balance detective work with motherhood.

After Dave Mendoza (guest star CHAD MICHAEL MURRAY) is injured in a drive-by, Ben takes is upon himself to solve the case - much to Sammy's dismay.

A breakdown in the dispatch system makes a difficult job even harder for the cops. Lydia reaches out to her old flame (MICHAEL JACE) and Cooper gets a new partner.

John and Lucero settle into their new friendship during a day filled with strange calls. While Ben and Sammy respond to an insane bank robbery call.

John thinks about life after the LAPD. Lydia connects with a man she sent to Death Row. And Sammy becomes a tabloid celebrity after a very public act of heroism.

The day's events bring all of our cops face to face with some of their greatest fears. A baby's death for Lydia: IA questions for Sammy; loneliness for Cooper; commitment for Ben.

John takes drastic measures to try to save Hicks while being confronted with demons from his past. Sammy's lie about the tape weighs heavily on his conscience. Lydia and Ruben track down a John Doe. Ben's relationship with Elena becomes more serious.

The funeral of a major drug dealer brings gangsters of all sorts out of the woodwork. With chaos in the streets, our cops learn that the greatest threats often come from within.

Chaos reigns in the city when Cooper and Lucero are kidnapped and held hostage by a pair of "tweakers" and our cops join the frantic search to find them... before it is too late.

In the season finale, John copes with the aftermath of his kidnapping, while Sammy closes in on the real robbers, Ben feels the pressure and Lydia becomes closer with Russell.