Kolchak, sitting on the bed of a sleazy hotel room, is listening to a replay of his dictation on his portable tape recorder. The notes are about a series of murders that have plagued the Las Vegas Strip, and a cover-up of those events by the authorities. All of the victims had their bodies drained of blood. When a meeting is conducted with the sheriff's department, the FBI, the police, and others, they discover the suspect's true identity is Janos Skorzeny, who is the prime suspect in multiple homicides extending back years, involving massive loss of blood. When Skorzeny attempts to rob a hospital, the police are called to stop him. Skorzeny is shot multiple times without effect, and manages to escape by outrunning a police car and motorcycle.

Kolchak's girlfriend, Gail Foster, a casino "change girl," urges him to explore vampire lore. The evidence persuades Kolchak to suspect that Skorzeny is a vampire, much to the disbelief of his boss, Anthony "Tony" Vincenzo. Following yet another failed attempt to capture Skorzeny, despite overwhelming police force, the authorities strike a deal with Kolchak to eschew their traditional investigative methods for his vampire-centric approach in exchange for giving him exclusive rights to the story. Acting on a tip, Kolchak locates Skorzeny's safe house and pursues the story on his own, fearful that the police will renege on their deal. Compromised when the vampire returns, Kolchak struggles to escape and is nearly killed by Skorzeny before his friend, FBI Agent Bernie Jenks, alerted to Kolchak's presence in the house, arrives and joins the fight. Realizing that dawn has broken, Kolchak and Jenks force a weakened Skorzeny back against a sun-drenched staircase and stake the vampire, just as authorities burst through the front door.

Kolchak writes his version of the story for the newspaper and proposes to his girlfriend, telling her that they will move to New York City. The authorities, however, unwilling to publicly admit that Skorzeny was the vampire Kolchak claimed, print a false version of the newspaper story with his byline and threaten to charge him with first-degree murder unless he quietly leaves Las Vegas. They also tell him that his girlfriend, Gail, has already been forced to leave the city for being "an undesirable element." Kolchak exhausts his savings placing personal advertisements across the country in a futile attempt to find her.

The final scene reverts to Kolchak in his sleazy hotel room. He explains that if anyone tries to verify the events in the book, they will find that all witnesses have either left town, are not talking, or are dead. He concludes by noting that Skorzeny and all his victims have been cremated, destroying any further ability to investigate the matter and eliminating the possibility that those killed by Skorzeny would in turn rise as vampires and perpetuate the curse.