Season 4

Detective Joe Barley enlists Holly, his "retired" snitch and recovering addict, to help him find the man who shot his partner.

Detectives Belmont and Melino want the three men involved when a patrolman, the son of a Lieutenant, is killed when he interrupts a bank robbery. The one they need is the psychopath who recruits amateurs in his capers.

Manny and Deke are on the narcotics squad, investigating a double shooting at a dry cleaning shop, when they get a tip that the shop owner is in business dealing drugs with a man called Mongoose.

Jack Mitchell is in control and keeps his cool when patrolling with his rookie partner, but his home life with his wife and her teenage daughter is not so tidy.

While working out his last three days before retirement, Frank Moran is assigned a hot case.

Lew Randle, head of the Special Investigations Team, comes back after vacation and is immediately engulfed in the investigations of several armed robberies. He has to buck department politics to take down the violent trio responsible.

K-Joe and Bunny investigate the sniper shooting of a young girl riding in a car on the freeway.

Gene (Santos) has a falling out with his wife and moves into a temporary bachelor's apartment, which becomes a party hangout for his buddies and attracts a lot of unwanted attention from others.

Sgt. Kyles and Inv. McLiam try to break up the criminal activities of a local entrepreneur and philanthropist by bringing back his past as a violent revolutionary in Detroit and playing on his paranoia.

Two detectives are called before the grand jury after a man is shot and killed when they attempt to arrest him.

Hagen and Triplett are reassigned to an out-of-the-way detail to keep them out of the public eye pending their manslaughter trial.

An undercover Vice detective is accused by one of his fellow Vice detectives of stealing cash during a drug bust.

Detectives try to track down the two remaining robbers who participated in a tire store holdup that resulted in the deaths of an employee and one of the robbers. Their investigation leads them to a large illegal weapons operation.

Holly Green, a 19-year-old waitress is brutally beaten and raped by a pair of creeps, she then reluctantly helps bring her assailants to trial.

Officers Webber and Cheruco discover a violent new gang on the streets, the Malflores, comprised entirely of Latinas.

Veteran Detective Jack McGraw is given the unsavory task of investigating Vice detectives suspected of taking bribes from the Chinese crime family running an illegal gambling operation.

LAPD Narcotics detectives work with a Mexican counterpart to try to break up the operation run by the Alvarez brothers, which is flooding the market with Mexican heroin known as "hard rock brown."

Detectives Gerard and Panelli try to catch a pair of armed robbers who hit a supermarket, and are joined by a one-armed former detective, who is now an investigator for the store's insurance company.

Sgt. Paul Cazenovia uses highly unconventional, albeit successful, methods in his undercover narcotics unit, but his lieutenant thinks he is crazy. It doesn't help that Paul refuses to stay behind his desk while he's under suspension.

Vice Detective Dave Tackleberry takes on a second job (to pay for his teenage daughter's figure skating development) at the same time he and his partner Det. Wurster try to bust a pimp specializing in underage girls.

Detectives DeHart and Ward go up against another team of officers Riggs and Salter in tracking down a criminal. A psychotic man is targeting elderly women and time is of the essence.

Marty Lacayo and Glenn Talbot are street narcs, meaning they are given the task of busting nickel-and-dime users and hustlers. Shep, one of their users, gives them a tasty lead on a big distributor, but they are forbidden by Lt. Hagedorn from pursuing him.