In the year 3000, the space salvage ship ''Mother III'' happens upon the derelict transport ''Demeter''. Captain van Helsing (Casper Van Dien) and his crew board the abandoned ship.
They explore the bridge and find the corpse of the ''Demeter's'' captain, (Udo Kier) tied to a chair and clutching a crucifix. Despite the misgivings of crew, intern Mina Murry (Alexandra Kamp) and vice-captain Aurora (Erika Eleniak), van Helsing claims salvage rights and decides to tow the ship back to Earth. As the crew prepares to return, ''Mother III'' suddenly uncouples from the ''Demeter'', leaving them stranded aboard the derelict ship with no means of communication.
Later, cargo specialist 187 (Coolio) and deckhand Humvee (Tiny Lister) discover a cargo bay full of coffins. 187 speculates that the coffins could contain smuggled goods and cracks one open only to find sand. Humvee heads back to the bridge while 187 stays to open the other coffins; he is soon attacked. The crew rushes to 187's aid only to find he is now a vampire. Under orders from his 'master', a mysterious figure, 187 attacks the crew, with Mina becoming his first victim.
Aurora, fleeing 187, runs into the "master" (Langley Kirkwood), a vampire named Count Orlock who bites her neck. Aurora makes her way to the recreation room; she reports her encounter with Orlock and reveals his intentions to return to Earth. Upon questioning, she is unable to explain how she escaped Orlock unharmed.
Thinking Aurora could be lying, the Captain leaves her tied up and guarded by Humvee. Soon, 187 gains entrance to the rec room and attacks Humvee, who manages to stake 187 in the heart with a wooden pool cue. Aurora, still tied up, confesses that she is in fact an undercover android cop investigating salvage activities. Van Helsing and Humvee feel betrayed but nonetheless untie her.
Searching the ship's database, the Captain and Professor (Grant Swanby), who uses a wheelchair, discover that the legendary vampire hunter Abraham Van Helsing was one of the Captain Van Helsing's ancestors. The Professor believes that Orlock will seek revenge against the Captain. The Captain learns from the ship's computer how vampires can be stopped and decides to steer the Demeter on a course towards a binary star system.
The Captain and Aurora are soon confronted by Orlock. While Aurora rallies reinforcements, the Captain fights Orlock alone, finally being overcome. Aurora and Humvee return, only to be attacked by Orlock. Aurora stakes him with another cue stick and wounds him but Mina (now a vampire herself) attacks, permitting Orlock to escape. Mina is dispatched by Humvee.
The Professor, despairing of his chances of survival, finds Orlock who promises to free him from his disability in return for aiding Orlock's return to Earth. When Aurora and Humvee return to the bridge, they find the Professor hiding, bite marks on his neck. Aurora stabs him with a cross, revealing that he was a vampire. A furious Orlock tries to enter the bridge but Humvee and Aurora manage to close the door on him.
As the ''Demeter'' draws closer towards one of the binary stars, Humvee and Aurora confess to each other that neither knows how to pilot the ship. They take comfort in the fact that Orlock's plans to return to Earth have been foiled. Aurora also reveals that from an earlier undercover assignment she is programmed for sexual pleasure.
The movie ends with a video segment from the Demeter's Captain Varna, who announces his intention to sacrifice himself and his ship; soon enough, the ''Demeter'' explodes in space.