Due to charges of using excessive force in apprehending criminals, homicide Detective, Katy Mahoney, is transferred to the ""Matron Squad"" in order to keep her badge. While following up on Paquito, a young boy she caught shop-lifting, Katy discovers the multiple homicide of two young women and some children. While investigating the murders, Det. Mahoney is discovers a connection to a family trafficking cocaine, which she investigates in spite of her superior having pulled her off the case.

After a woman is murdered at a housing project known as ""The Heights"" Katy learns that Alvin Banger and his gang have the tenants living in fear. They have kids stealing from stores and people's homes and use the Heights as their base of operations. Katy becomes determined to break up Banger's empire

As a war escalates between two street gangs, The Latin Lords and The Demons, Tommy and Julie find love. Unfortunately each is related to members of the opposing gangs. Katy encourages Tommy to make the right choices, which might make it possible for the star-crossed lovers to have a future together.

Katy Mahoney tracks a serial killer while investigating a string of South Side murders.

Katy Mahoney searches for a Vietnamese assassin who is programmed to kill former soldiers and refugees who have moved to America.

Katy Mahoney investigates a series of murders committed with unconventional weapons and poisons.

An imprisoned criminal mastermind hires hit men to kill everyone responsible for his conviction, starting with Katy Mahoney and her former lover.

While infiltrating a terrorist organization, Katy Mahoney discovers that their main objective is to dismantle Chicago's political system.

Katy Mahoney is injected with a hallucinogen during an encounter with a drug dealer, and wanders around the city having strange visions.

While tracking down a hit man who kills local drug kingpins, Katy Mahoney discovers that he is part of a larger plot to establish an international narcotics operation.

Katy Mahoney is tasked to find a former Green Beret and his gang, who are killing people for thrills.

During an investigation, Katy Mahoney discovers that a policewoman was murdered to cover up a scandal involving politicians, pornographers, and bankers.

Katy Mahoney and detective Gino Gianelli are kidnapped by a group seeking vengeance for an arrest.

While searching for Terry McNichols' missing niece, Katy Mahoney becomes involved with a group of cowboys trying to steal a shipment of bull semen.