An alliance between a detective and a criminal create deadly consequences.

The investigation of a police officer's murder shows he is allied with a notorious criminal.

The officers must investigate the murders and rapes of new mothers.

A shooting at a dance club leads to a family being murdered.

The discovery of a a buried skeleton reopens a 25 year old mystery.

Bodies of women are found in a warehouse.

Mistaken indentity is the probable cause of a drive-by shooting.

The officers must investigate the death of a student who was found in a subway station.

The Russian Mafia is suspected of a celebrity's shooting.

The officers discover that mysterious deaths at a hospital may be somehow linked with unsolved deaths.

A racial killing is suspected when a black civilian is shot.

The investigators must find some link between an anti-abortionist group and the murders of abortionists.

The officers must investigate an assault on two women.

A psychiatrist is found murdered at a criminally insane hospital.

A failed bank heist brings low police morale to the surface.

When a politician and his wife are found dead, the squad initially suspects that it may be a murder/suicide.

The police investigate a crime-suspected adoption company.

The homeless living on the streets are the target of a murderer.

A connection is found between a biker's murder and a mobster's murder.

Four accountants are murdered, and the investigation leads to a maze of possible murderers.

Oosterhius is convicted of a murder.

Castillo and Sweet try to track down some kidnappers that have given the team 36 hours before they rape the kidnapped child.

Sweet and Castillo investigate the racially motive package bombs that kill Carlotta Alcantara and Martin Simpson, and find themselves dealing with a suspect who ignores Sweet because he's black and is equally dismissive of the Hispanic Castillo. It isn't long before they realise Carl Purdy's motive is connected to his ex-wife's new Cuban husband. Pogue and Oosterhuis investigate the death of political intern Tammy Moore, who was found hanged and dressed in bondage gear by an underpass. Their investigation leads them to the Club de Sade, whose owner sends them right back to the lawyer who had sworn Tammy was too freaky for him.

A raped woman is found in an abandoned building, and the pattern looks like a crime that Castillo once failed to solve.

After the serial rapist is found murdered and evidence shows he was killed by a woman, Castillo and the rape victims are prime suspects.