Elvis Cole agrees to work with his partner Joe Pike to find Karen Garcia, a former girlfriend of Pike's, who has gone missing. Soon, they learn that her body has been found by the Los Angeles Police Department in Lake Hollywood. Karen's father, Frank Garcia, begs the two private detectives to work with the LAPD to catch his daughter's killer, and Cole and Pike agree. Harvey Krantz, the lead detective for the LAPD, hates Joe Pike and refuses to cooperate with Cole, but Garcia insists that the two men remain involved.

Pike's history with the LAPD prevents him from working productively with the police force, so Cole goes the Parker Center and meets Samantha Dolan, a clever, tough cop who resents having to baby-sit the unwelcome private detective. Soon, Cole realizes that there is more to this murder than meets the eye, and he learns that Karen Garcia is actually the fifth victim to be killed by the same serial killer in the last two years. Krantz admits that the Robbery-Homicide unit has been tasked to discover the identity of this killer, and he confesses that he suspects Eugene Dersh, one of the two men who discovered Karen's body. Cole and Pike both doubt that Dersh is a serial killer.

Meanwhile, Pike recalls much of his painful childhood, the time that he spends in the military as a young man, and his relationship with Karen Garcia, which ends when Karen realizes that Pike is in love with Paulette Wozniak, Pike's partner's wife. Pike is a notorious former cop that many other police officers would love to see incarcerated, so when Eugene Dersh is shot and an eyewitness puts Joe Pike at the scene of the crime, Krantz relishes the opportunity to arrest his longtime rival.

Cole continues to work towards finding Karen's killer, but his personal life suffers. Samantha Dolan expresses interest in Cole, but he has a long-term relationship with a lawyer named Lucy who has recently moved to Los Angeles to be closer to Cole. He attempts to keep Dolan at an arm's length out of respect for his relationship, but his attraction to her makes it a constant struggle. Once Pike escapes from prison, Lucy loses faith in him, and her doubts hurt Cole deeply. Their relationship falters under the intense stress of Cole's work and his refusal to make her a priority.

Cole and Dolan continue the investigation on their own, learning that the six victims all testified against Lennie DeVille, a pedophile who Pike and his partner arrested right before Wozniak killed himself. They soon uncover the identity of Laurence Sobek, a young man who had lived with DeVille before DeVille died in prison and who has been working at Parker Center under another name for the last two years. Sobek is their killer, but they must find him. The Robbery-Homicide team raids his house, but he has booby-trapped the apartment and Samantha Dolan dies in the operation. Cole fears that Sobek may try to kidnap or kill Lucy and her son, but then realizes that he wants to kill all of the people who hurt DeVille. He has gone to kill Abel Wozniak's widow.

After a shoot-out at Paulette Wozniak's house, Cole and Pike are both shot and Sobek is killed. The cops can tie Sobek to all the murders except Dersh's, so Pike must run from Paulette's house. Cole helps him escape, and so along with getting a physical wound, he loses his private detective license and his relationship with Lucy. Soon, however, Cole connects Sobek to Dersh's murder, and Pike's name is cleared. Frank Garcia helps Cole regain his detective license, and Cole feels hope that he may redeem himself to the woman he loves.