American siblings Max and Chris Townsend are left behind in Europe with their eccentric uncle Gustav while their mother Eileen travels on business. Max, an enthusiast of the supernatural, is positive that his uncle is a vampire and seeks out multimillionaire Alexander Lucard for help. Little does he know that the businessman is hiding a secret of his own...

Gustav's old friends Peter and Anna Dyson come for a short visit while Max takes the Cross of the Magyars—an artifact that prevents vampires from entering—from the house to be blessed. When Lucard learns the cross has been removed, it is a race to see whether it can be replaced before Lucard comes calling; but how did he find out that it was gone?

Gustav and former student Arthur Bauer locate a rare herb and develop a formula in hopes of reversing the effects of a vampire's bite. To test it, Gustav allows himself be captured and bitten by Lucard, unaware that the formula accidentally switched with Max's protein drink.

Max brings home bungling vampire-hunting scientist Magnus St. John-Smythe, who insists that a new laser gun he's developed can destroy vampires. Unfortunately, his 'anti-vampire gun' is being sponsored by Lucard.

Archeologist Dr. Gloria Cross uncovers the resting place of Lucard's ancient and bitter rival, Nosferatu.

Paul Yeager, an aggrieved husband, asks Gustav to kill Klaus, the vampire who has taken his wife... and Lucard's second-in-command. Gustav, however, has a different plan in mind for Klaus, as they share a horrifying relationship.

When Gustav learns that Lucard is buying an old local cinema, he investigates to find out what the vampire's true interest is in the place.

Eileen is doing business with Lucard; in fact, she's going to have dinner with him at the castle. Gustav and the kids learn of the dinner, but Gustav himself is vampirized by one of Lucard's assistants, and the kids are left on their own to rescue their mom.

Gustav appears on a TV talk show to debunk zany psychic Lana Zorro, whose knowledge of Gustav's past grows increasingly terrifying. Meanwhile, Max is sure he's discovered the resting place of Dracula and can therefore destroy him.

Encouraged by Gustav, Chris decides to take his rock music to a live audience. Meanwhile, Sophie becomes a guide to an influential Contessa who has business dealings with Lucard.

Chris lands a job with a local art house, run by a lovely dealer named Julia, who happens to have dealings with Lucard.

Lucard invites Mycroft Tickler, a lounge performer with delusions of grandeur, to give a recital at his castle. Gustav tries to warn Tickler, but he's utterly oblivious to anything other than the chance to further his career. However, Lucard actually has no interest whatever in Tickler's 'talents'; he knows that Tickler is none other than Magnus St. John-Smythe's brother.

Lucard bites a teenage thief, unaware that he has a rare antigen in his blood that can kill the vampire who ingests it. Famed vampire doctor Gabor Varney informs him that there is only one cure: water from the Paquette Spring in the Bettange Valley. Sick and delirious, Lucard doesn't trust anyone, and insists on going himself. Meanwhile, Sophie is dating a creepy young existentialist poet who turns out to be the thief whom Lucard bit.

Following her romance with Vincent, Sophie has been turned into a vampire, and is serving an apprenticeship with Lucard. Mrs. Pfenning, Lucard's accountant, is plotting to overthrow her master and wants Sophie's help. Meanwhile, Gustav finds the key to restoring Sophie to her human self in Vincent's unusual blood type, and Chris is able to introduce the solution into her system with a kiss.

Having been rescued by Chris, Sophie is about to fall for him, but his ex-girlfriend Alexa Singleton turns up, whose obnoxious businessman father is in business with Lucard and makes the mistake of underestimating him.

Gustav's best friend, a fellow vampire hunter named Frederick Rilling, claims that citizens at his retirement home are being killed by a vampire. He asks Gustav to help him destroy the perpetrator. Meanwhile, Lucard tries to play Pygmalion to an airheaded Galatea named Amber Santana.

Max inadvertently frees Klaus from the Helsing family crypt where Gustav had imprisoned him, and Gustav and Lucard try to escape his trap. The powerful Cross of Silesia and a plastic explosive will destroy Klaus's two fathers at the same instant unless they work together to outwit him.

An old love from Lucard's past, Margo Burton, comes back into his life, only now she's married to a writer whose latest work is intended to expose Lucard as a vampire and bring down his empire.

Max meets Lawrence Lei, a creepy and neurotic bookseller who has a peculiar interest in the occult. Gustav doesn't trust him, and Lucard finds him much too bizarre for his taste when he shows up at the castle, asking to be turned. Lawrence mentions that his friend Alfred won't make him a vampire either, and Lucard decides to hunt down this Alfred, whom he suspects is responsible for the recent upsurge in the area's population of inferior zombies.

Gustav, Max and Chris are invited to dinner at Lucard's for a reminiscing, but is there an ulterior motive to this sudden hospitality?

When Eileen arrives at the end of summer to pick up Max and Chris, they learn that she has a new business partner: Klaus. Gustav discovers a time hole in the castle that keeps Lucard young.