A woman is brutally murdered in her daughter's room at a shelter for battered woman. Her daughter, Julie, is a traumatized eyewitness to the slaying and identifies her father as the killer. Despite her account, Nick and Tracy are unable to find enough evidence to hold or indict him. As they search for the truth, an "avenging angel" decided to take justice into her own hands.

Soon after a psychopathic killer, Peter Barlow, escapes from a mental institution, a patient's body is discovered on the hospital grounds -- the victim of a brutal and vicious murder. The following day another patient's body is discovered. Both crimes match Barlow's M.O., and Nick Knight is determined to prevent another murder. But, Nick's quick arrest of Barlow proves there is a different killer at large. Now he must find a new connection between the victims and the murderer.

When Nick saves Schanke's life during a fire fight, Schanke can't help but notice Nick has taken up flying. Despite Nick's hypnotic suggestion to forget what he saw, Schanke begins investigating Nick's past. Natalie can't deflect him and Janette's attempts to hypnotise him fail. The trail soon leads him to conclude his partner is a vampire and from there to LaCroix. The question is, what is LaCroix going to do with the inquisitive Schanke?

Nick investigates the death of a young doctor when Natalie is unable to determine the cause. Intrigued by the doctor's experiments in near death experiences, Nick secretly agrees to "go under" in an attempt to reconcile his own past. But the experiment goes awry and Natalie must find a way to bring Nick back form his altered state of consciousness.

David Constantine is the next in line to become "Don" of the city's biggest crime family, but after witnessing a lifetime of killing and bloodshed, he just wants to live a normal life with his family. Nick Knight understands David's dilemma, as he wants to get away from his self-proclaimed father, LaCroix. However, David's great grandfather will stop at nothing to ensure his grandson's enshrinement, even going to LaCroix for help. This sets up a Father's Day showdown between David and his great grandfather and Nick and LaCroix.

After a model missing for four months is found dead under mysterious circumstances, another model disappears who bears a striking a resemblance to a dancer Nick fell for a long time ago

Someone's calling CTOK radio's on-air psychiatrist and murdering women on the air. Dr. Noble comes to Nick's aid -- to Stonetree's dismay -- while Schanke searches through psychiatric records. Noble thinks the killer is acting out a murderous fantasy -- one that may involve her.

The investigation into Stonetree's recent shooting of a perp is keeping him up nights. Meanwhile Nick confronts a ghost of his own -- one that's about 300 years older.

Nick and Schenke are protecting a musician who is being threatened.

Serena, a victim of Nick's immortal bite from the past, has a plan to regain her mortality. According to ancient legend, a vampire will become mortal if she bears a mortal's child. But to conceive, the mortal must possess an extra chromosome and will be murdered soon after conception. When Trilling, who possesses the magic chromosome, is arrested for murder, Serena provides an alibi to get him out of jail. Fully aware of Serena's plan, Nick struggles to solve the murder -- torn between reconciling the wrong he did Serena and preventing yet another murder. But his actions, along with the reasons behind them can never be revealed.

When the head of a team of astronomers is commits suicide, their predictions of a meteor's collision become public. As panic sweeps the world both mortal and vampire populations face their personal fears. Some of those fears lead to unusual actions.

Nick investigates three woman who are member of the Spa Experience. They're all young, beautiful, and have murderous tendencies, but do they share something more than skin deep?

The two day search for Natalie Lambert's young niece ends when the missing girl's body is discovered in the woods. After Nick Knight rescues the alleged killer from an angry mob of vigilantes, a blood test and line-up fail to provide enough evidence to hold him. Removed from the case because of her ties to the victim, Natalie questions the results of the lab work. When the suspect suddenly dies, Natalie performs her own lab test and uncovers another murder.

Natalie's research leads her to believe she might be able to cure Nick, if he's willing to take the risk. While taking the wonder drug, Nick and Schanke unofficially investigate the suicide of another cop. Is Nick just having incredible hunches or is the drug not quite what it seems?

When an anonymous tip leads NIck to a "headless corpse" in the Raven, it is only the beginning of a deadly game, with vampires as the target. Nick soon discovers the ultimate target in these murders is LaCroix. Anyone and everyone who is close to LaCroix are being killed. When LaCroix reveals that the perpetrator is Divia, his daughter and master who he betrayed long ago, it becomes a race against time for Nick to find her before she comes for him or LaCroix.

Nick is amazed when a police sketch composite for a murder suspect looks remarkably like Janette. Then Janette suddenly shows up again in his life admitting to the murder and asking for his help. As Nick struggles to discover the truth behind Janettes behavior, he puts his career on the line for her. When he discovers her secret Nick is faced with an impossible choice.

A scientist is murdered and a lab rat escapes when industrial espionage goes awry. But far worse things begin to happen when the lab rat, infected with a newly engineered virus becomes Screed's next meal. Designed to combat HIV, the virus becomes lethal to vampires as it multiplies and intensifies each time they "feed". As the virus spreads rapidly through the vampire community, it infects Vachon, Nick, and LaCroix. Nick races agains time to find the killer - while Natalie struggles to find a cure.

A bullet wound to the head lands Nick in the emergency room, where with no pulse, no heart rate, and no brain activity, he is declared dead. Fast action by Natalie and LaCroix, brings Nick back to life. While his physical wounds are healing, his mind is another matter--he has amnesia, and therefore no memories of who he is or what he is. Both Natalie and LaCroix see this as a chance to acheive their goals for Nick. Who will win this little contest, and what will be the price? Meanwhile, Nick must find the killer before he strikes again, as well as find out who he really is.

Upon leaving his wife, Schanke moves in with Nick, expecting to lead a wild bachelor's life with his partner. But the two are soon at odds over the investigation of a wealthy business-man's murder. Feeling that Nick is once again trying to keep one step a head of him, Schanke vows to solve the case on his own. Acting on a sudden revelation while drowning his sorrows in liquor, Schanke rushes to apprehend the murderer without his partner and captures the killer single-handedly. Or, so he thinks.

When Schanke's ex-partner Delehanty shows up, his rich, comfortable, and "warm" life in Arizona, gets to Schanke's winter-worn heart. When Schanke and Delehanty conclude that a series of deaths are the result of product tampering, Nick's hunch about the case drives a wedge between him and Schanke. When Schanke refuses to listen to Nick, he must solve the case despite Schanke and Delehanty's conclusions, and before Schanke decides Arizona might be the place to be.

A serial killer who appears to get women completely in his control before killing them is on the loose. But he may be untouchable since it looks like he's a diplomat. Nick's past experience with people who abuse power indiscriminately may make him step over the line in pursuit of justice.

A suicide of a friend and colleague causes Natalie to reexamine her life and her feelings for Nick. Nick, too, is dealing with the loss of a friend, and his own feelings and reactions. When Natalie confronts him, Nick makes some decisions that will have far-reaching implications in all of their lives.

When Nick efforts to stop a robbery without using his "vamp" powers causes a death, he becomes consumed with guilt. Nick's life seems to spin out of control and nothing seems as it is. Things truly become curiouser and curiouser.

Nick joins the Luminology cult to investigate the death of a city official's son. When he inexplicably breaks off contact with the department, however, Natalie infiltrates Luminology's headquarters and discovers that Nick has been brainwashed.

Life imitates fiction when Emily Weiss, the best-selling author of a series of vampire novels, is attacked by a crazed fan. Her works are amazingly true to life, leading Nick to believe that she may know more about the vampire community than she says. LaCroix, the leader of the community, sees her as a threat and declares that she must die and Nick must carry out the decree. Nick, however, finds that he is falling in love with this woman. She is the only mortal capable of understanding what it is like to live in eternal darkness, and she would go willingly into his waiting arms if asked. The time has come for the truth and the fiction to become one, and her fate rests in Nick's hands.

When a serial rapist is ripped to shreds by a dog, Natalie suspects that something isn't quite right. Nick's investigations leads him to suspect a carouche, a lower form of vampire who typically feeds on vermin, may be behind the dog's behavior. When Nick finds the dog, he discovers that it is the devoted companion of a blind dispatcher. Now he must figure out how to protect the dispatcher (and everybody else) from her not-so-mortal dog.

While investigating a series of bizarre murders, Nick discovers that an ancient evil from his past is behind the crimes. LaCroix, his former vampire master, has returned to the city in search of Nick, his one-time pupil The murders, coldly orchestrated by LaCroix, threaten to uncover Nick's sinister secret when he is arrested as the prime suspect. With the help of his partner, Don Schanke, and the department pathologist, Natalie Lambert, the only mortal who knows his true identity, Knight escapes. Now an outlaw, he must track down the killer and find LaCroix before he is forced to give up his dream of regaining his mortality.

Valentines day not only brings out a killer who lures in women with romantic cards, but turns Nick's thoughts to Natalie, and LaCroix's to past love. All this love in the air is bound to be dangerous.

A crazed killer using a flame-thrower to torch his victims sends Nick and Schanke on an underground pursuit. In the confined quarters of the underground sewer system, it's anybody's guess who will find who first. While Nick faces his fear of fire, Natalie discovers she has her own fears to deal with.

A journalist covering the mayoral election is electrocuted in his hotel room. Later his girlfriend is found dead too. It appears one of the candidates may be involved in a sex scandal. Can Nick find out who committed these murders without engaging in a witchhunt? Dirty politics and mudslinging gets Nick thinking about when he was Professor Nicholas Girard (Chicago, 1954) -- and on trial before the HUAC on charges of being a Communist.

While investigating the murder of a virtual reality software designer, Nick finds the vampire game he created fascinating. Inside the game, Nick finds the killer waiting, daring him to try and find him. Playing the game he searches for clues, but finds himself intoxicated by the vampire feeding instead, feeling his lust for blood and killing reawaken. The closer he gets to solving the crime, the closer he gets to wanting to losing control and killing again.

Nick goes undercover to investigate the murders of members of The Twelve Steps, a support group for addicts. Can his sponsor help him with his addiction, or is she out to kill him too?

When an airplane transporting a bombing suspect and Schanke explodes, Nick becomes racked with guilt. He feels it should have been him on the plane and not Schanke. Nick turns in his badge, ready to move on to a new life. He decides to return when other police stations in the city start exploding.

Nick and Schanke apprehend a convicted murderess on the run from Texas authorities when an anonymous tip leads them to a rental car agency. Nick believes she may be innocent, however, he must prove it before she is extradited and put to death for her crime.

When Nick is unable to obtain a harp with magical properties tied to his mortal past at auction, his actions are less than legal. When the auctioneer is found murdered, Nick finds himself in a precarious situation, caught between the harp's longing and his own desires.

Nick discovers an ancient, terrifying evil is behind a series of grizzly murders plaguing the city, and he may not be able to stop it. He is unknowingly paired with Chief Inspector Liam O'Neal of Dublin C.I.D., a vampire hunter with a dark secret, who has tracked the murdering creature's bloody trail half way around the world. Wary of O'Neal, Nick begins an investigation of his own, learning the Chief Inspector's true identity, as well as that of the killer -- Jack the Ripper -- a vampire created by LaCroix. Nick had a chance to destroy the Ripper a century ago, but turned his back, unleashing a century of carnage around the world. He must now put aside his guilt and finish the job, but in doing so, O'Neal may finish him.

Someone is killing a number of homeless people and draining their blood. Then a museum guard is killed the same way and a special artifact is stolen, a Mayan cup that Nick believes can help him become mortal again. Nick suspects that his old mentor Lacroix is in town and behind the murders. Forced into a partnership with the unbearable Detective Schanke, Nick has to face both Lacroix and the Homeless Killer while trying to protect his friends.

Nick's feelings of responsibility for the death of a man he was supposed to protect in a "sting" operation causes him to lie about actually seeing the murderer pull the trigger. In addition to the problem of having to appear in court to testify in broad daylight, Nick's desire to see justice done struggles with his conscience. He calls up memories of an incident from the past in which a woman lies in court, condemning to death a man Nick knows to be innocent, since he saw his fellow vampire Janette commit the crime.

Schanke's old partner is gunned down in the street. The bad guys make it clear Don is next. Jeanette lets Nick hide Schanke at The Raven because his predicament reminds them of when Nick, Jeanette, and Lacroix were hunted- only this time it appears to be an inside job.

A drive-by shooting could ignite a gang war, but Schanke's got stars in his eyes moonlighting on a movie set. Then the star of the movie steps right into the killer's path. Will Nick and Schanke find the renegade killer before this movie star is history?

A patron of the Raven is found dead, apparently killed by a vampire in unusual circumstances. The woman at the scene has no memory, and there are no clues. Nick must find the vampire-killer before he strikes again, while keeping Tracy out of trouble. For Tracy is aware it is a vampire, and is searching for the killer, too.

When a murder occurs in a haunted house, it looks like the murderer might just be ... a ghost. On top of the investigation, Nick, Natalie, and Tracy all encounter ghosts from their own past after being in the house. When another man is apparently killed by the hand of the ghostly murderer, Nick and Tracy suspect their ghost may not be so dead. While they hunt for the murderer, all of them are haunted and must find a way to come to terms with their own ghosts.