British estate agent Renfield travels to Transylvania to meet with the mysterious Count Dracula, who is interested in leasing a castle in London and is, unbeknownst to Renfield, a vampire. After Dracula enslaves Renfield and drives him to insanity, the pair sail to London together, and as Dracula begins preying on London socialites, the two become the subject of study for a supernaturalist professor, Abraham Van Helsing.

A countess from Transylvania seeks a psychiatrist’s help to cure her vampiric cravings.

Carpathian Count Alucard is invited to the U.S. by a young heiress. Her boyfriend and local officials are suspicious of the newcomer, who is interested in the "virile" soil of the new world.

A scientist working on cures for rare afflictions, such as a bone softening agent made from molds to allow him to correct the spinal deformity of his nurse, finds the physical causes of lycanthropy in wolf-man Larry Talbot and of vampirism in Count Dracula, but himself becomes afflicted with homicidal madness while exchanging blood with Dracula.