During a routine day, Detective III Shane Scully accidentally strikes John Bodine, a homeless schizophrenic African America man with his car.

A series of leads eventually finds Scully interrogating Lou "Luna" Maluga, a psychotic sociopath, and his estranged wife Stacy, the titular "White Sister," both big names in the rap music industry.

Later, his son will point out that the majority of the text are veiled references to several rap slang terms and groups, making the messages coded transmissions from the undercover officer.

During this time, he receives a phone call from Alexa where she confess to the murder and apparently commits suicide, leaving her in critical condition.

Stacy, after confronting Scully and explaining how this doesn't affect her plans, is shot by her bodyguard "Insane Wayne," an undercover California Sheriff's officer.