An abandoned church near August's home explodes into a fireball, triggered by an illegal methamphetamine lab. The next morning, he and Chase confront a group of bikers while trying to arrest one of them, and the bikers' trailer erupts into flames. It was being used as a meth lab. It's apparent somebody wants the labs out of business. Determined to crack the case, the detectives team up with Annie Mason, a new forensics assistant at police headquarters. Annie is able to turn up a suspect, a dangerous biker called the Falcon, with a rapsheet a mile long. But when he checks out the man's file, August is shocked to recognize the Falcon as Robert Hatcher, his former partner.

A young woman is found murdered with fang marks on her neck, her body completely drained of blood. Chase and August attempt to question a suspect dressed as a vampire, but he takes off in a hearse, leading the detectives to a warehouse. They interrupt what appears to be a blood-drinking ceremony with a group of men and women, all dressed as vampires, and bring several ""vampires"" in for questioning. Wanda, the attractive leader of the group, falls for Chase and wants to protect him from the suspect they originally chased, who may not be what he thinks he is, but who may be just a dangerous.

The bodyguard of a famous actress, known for her seductive, deadly roles in low-budget B-movies, is murdered, and Chase and August are on the case. As the investigation progresses, the actress, considered a suspect, shows an interest in Chase, who has been ordered to protect her. But the real suspect could be closer than they think, and the least likely of them all.

A van filled with illegal Mexican immigrants crashes in a violent explosion, killing many of its stowaways, and Chase and August arrive on the scene. Survivors limp with cuts and bruises, but the smuggler, the Coyote, has disappeared. One of the survivors tells the detectives that a man named Delgado had smuggled them across the border. Det. Maria Vallejo connects Delgado to a suspected sweatshop owner, and the detectives reluctantly put her undercover.

A judge, a housewife, and an attorney are all killed by toy-like devices. While searching for the victims' possible connection, Chase and August discover that all three were involved in a court case years earlier in which a woman, working in a college laboratory, was killed in an explosion set off by a radical activist. At the conclusion of the trial, the killer was set free. Afterwards, the woman's husband, Karl Shipman, set out for his own revenge. After killing the man who killed his wife, Shipman was arrested and sent to prison for life. But Shipman wasn't finished with avenging his wife's death yet, and gave the orders for murders from prison.

A group of Nazi skinheads demonstrate outside a black church, and a riot is narrowly prevented as Chase and August arrest a skinhead and a churchgoer. The next week, the church is burned to the ground, and a charred body is found inside - Duke Minks, a member of the Aryan Nation, who was arrested during the demonstration. The victim's uncle, Eddie Minks, also a member of the Aryan Nation, isn't happy that August is on the case, and warns that justice will be served, one way or the other. As the detectives dig deeper, they learn that the arsonist may be the person they least suspect.

Michael Mills, a convicted killer, escapes from prison and seeks revenge on the three cops who put him there. He kills two of them and goes on the hunt for the third, August Brooks, who has gone camping with Kendra for two weeks. Chase is still in Los Angeles, investigating the murders of the two officers. After putting the pieces together, he realizes that August is in danger and tries to find him at the remote campsite where he is vacationing before Mills does.

Art thief Richard Turpin, known as the Gentlemen Bandit, crawls through the skylight of a Los Angeles museum, only to be caught in the act by Chase and August, who apprehend him and haul him off to jail. The British government decides to extradite Turpin, accusing him of association with a radical faction of the IRA. Scotland Yard detective Wilhemina ""Willy"" Smythe arrives to collect Turpin, but her plans are soon thwarted when a terrorist named Riley shows up, who has plans of his own for the thief.

Chase and August arrive at the scene of a murder at a mental hospital, where a prominent psychiatrist has been stabbed to death. The suspect is a patient, Treat Donnelly, who is revealed to be Chase's cousin and vehemently denies killing the doctor. Several of Dr. Benning's colleagues fall under suspicion, and the plot thickens when it is learned that Elaine Hall, the dead doctor's beautiful assistant and one of the suspects, has more than one personality.

Danny Bledsoe, a key witness set to testify against crime boss Alfredo Matessa, is escorted to Los Angeles by Nicole Stockman, a beautiful tough-as-nails detective from San Francisco, where he had fled to. From the start, Nicole makes it very clear to Chase and August that she resents doing all the work to catch Danny in San Francisco, only to have them receive all the credit during the L.A. trial. And Danny isn't known as ""The Eel"" for nothing. As Chase and Nicole are transferring Danny to a safehouse, he escapes. Afraid that the police can't protect him from Matessa, Danny decides to take his chances on the streets. With time running out, Chase, August and Nicole have to catch the Eel before Matessa's thugs do.

Chase and August investigate a gun-running operation in which the prime suspect turns out to be recently-murdered CIA operative James Camden. Chase is seduced by Camden's former partner, but the romance is cut short when he discovers she may be involved with the plot as well.

Detectives August Brooks and Chase McDonald meet when August and several officers are being overwhelmed by criminals in an explosive shootout. Chase arrives in his Porche and immediately neautralizes the situation with a grenade launcher. Moments later, August discovers that Chase is his new partner, and they are immediately assigned the case to track down a bomber - nicknamed the Daybomber - who has set off a series of explosions in his quest to warn people of the advances of technology.

Arriving at the scene of a murder, Chase and August find that the victim is Bobby Roman, a favorite target of controversial shock-jock Jerry Maxwell. Roman has been shot in the head, just as Maxwell always advocated. When Chase and August confront Maxwell about the murder, the beligerent radio host denies involvement in the crime. But then a call comes into the station, and Maxwell is shocked to hear a devoted listener, Ward Valasco, claim that he killed Roman, and that he intends to kill all of Maxwell's enemies.

Teenagers Alan and Ian cruise down a city street smashing mailboxes, while Harold's younger brother, Ian, is forced to videotape their antics. The two older kids' thrill-seeking escalates when they smash the window of a store and accost the cashier. When the cashier opens fire, both he and Ian fall to the ground, and the other two take off running, Harold throwing the video camera into a dumpster before being caught by police. August and Chase question Harold at headquarters, but he has been threatened by Alan not to talk, or he and his mother will be killed.

When former stars of the popular 1960's television show ""Captain Crimestopper"" are murdered, August suspects the show's star, out-of-work actor Wayne Berry, but Chase refuses to believe that one of his childhood heroes could be a murderer. At one of the crime scenes, the detectives apprehend a man disguised as the superhero, who turns out to be Berry himself, intent on finding the killer. When forensics concludes that Berry is not the killer, the actor is released, but an attempt on Berry's life at an autograph-signing puts the detectives on the trail of the one responsible.

Leonard Murdoch, a scientist for the high-tech firm Biotech, is murdered, and Chase and August suspect someone in his company wanted to keep him quiet. The detectives get a call from a Biotech whistleblower who tells them that the firm's CEO is planning to sell a top-secret biological chemical to international American enemies. Chase is convinced it's a cover-up for a government study of alien DNA, but before he and August can learn more, they are surrounded by military vehicles and men in black.

Chase and August are at August's gym, where they are volunteering their time to help keep kids off the street and out of gangs. In the boxing ring is Andre, a young fighter determined to stay away from gang violence. But when word comes in that Andre's brother has been shot and killed by a rival gang, Andre swears to avenge his brother's death. Chase and August try to persuade him to let the police handle it, but Andre slips from their grasp in pursuit of the killer. The incident also brings back memories for Chase, who is struggling with unresolved guilt over his former partner's murder by a gang youth.

When a wealthy foreign couple touring L.A. are found murdered and robbed, Chase and August are assigned to investigate. What they don't know is that these are not random killings, and that Russian mobster Ivan and his gang are plotting more crimes. The FBI demands that Chase and August focus only on the homicides and leave the robberies to them, but the detectives believe the two crimes may be connected.

Having just finished lunch in Chinatown, Chase and August are preparing to head back to the station when they see a drug deal going down. A chase ensues, and the detectives split up. When August finds Chase, he is lying in an alley, unconscious, with one of the men lying next to him dead. An eyewitness says she saw Chase kill the unarmed man, but Chase can't remember what happened before he was knocked out. August feels certain his partner is innocent and sets out to uncover the truth while Chase is suspended.

Chase and August investigate the murders of two men: one an affluent, politically-connected businessman and the other a homeless man. They discover that the homeless victim was once a successful businessman who was going to testify against infamous criminal Bobby Cole. But the man was beaten so badly he forgot his identity and ended up on the streets. The detectives race to uncover Cole's secret before his hitman makes them the next victims.

August goes undercover as Jake Rheams, a notorious East Coast drug lord, who arrives in Los Angeles to make a deal with the Carletti crime family. August meets with Gina Carletti, the beautiful and seductive daughter. Alex Zota, the boss' right-hand man, suspects August from the start, never really believing that he is the real Jake Rheams. Meanwhile, Chase must back up his partner the best he can, including an interrogation with the real Rheams, who is being held at the station. August is tested by Zota, and only Rheams has the information that can help Chase save his partner's life.

A Western memorabilia collector is found murdered, and among the victim's belongings is a laptop containing August's name. August figures out that his name was listed among the descendants of Buffalo Soldiers, a special troop of black soldiers that fought during the Civil War. This brings up a part of August's past that he is ashamed to discuss: his great-great-great-grandfather, Augustus Brooks, was given a dishonorable discharge from the Army when he allegedly deserted his troop with three other soldiers, claiming to have been given a map leading to a gold mine that was never proven to exist. August's Aunt Maisie is attacked in her home by a thug, hired to steal a portion of the old map. The pieces have been handed down to each generation, and now someone is attempting to put the pieces together and lay claim to the gold.

A prisoner named Murnau, who blames Chase for the death of his brother, is en route to prison when he escapes. Responding to the emergency call, Chase and August catch up with Murnau and pursue him. Their high-speed chase leads them onto a film set, which is being prepped for a car stunt. Both cars crash on the set, and Chase is knocked unconscious. In the hospital, friends and family visit the detective, hoping their voices will help revive him. Elsewhere in the hospital, Murnau plans his own visit to Chase.

Chase and August are escorting an annoying accountant named Cecil Rusk - the star witness for the prosecution in mobster Marius Roma's tax evasion trial - to court when they are ambushed by Roma's brother and his thugs. After their car is destroyed, the trio escape on foot through a hail of gunfire. Alone on the streets of Los Angeles, they decide to head out of town, where they believe they'll be safe. But a mole inside the force is leaking information on the detectives' whereabouts to Roma's mob, and it's up to Captain Jensen and Det. Richardson to figure out who it is.

Chase and August are eyewitnesses to a young man who throws a Molotov cocktail into a car right outside the gym. The perpetrator gets killed in the ensuing pursuit, but they find out that the car was registered to Carlos Altamarino, a known drug dealer. Chase is visited by an old college friend, now a CIA agent, who gives Chase a mysterious gold key for safekeeping and reveals that Carlos' operation has shifted power to a brother, a cousin, or perhaps even Carlos himself using an alias. The new boss carries the name Charlie Altamirano. Chase's friend is killed later, and the detectives work to figure out just what exactly is going on.