Real estate agent Jonathan Harker is sent to Transylvania to the castle of Count Dracula, who has expressed a desire to purchase a mansion in Germany. Upon arrival at the count's castle, Harker signs all the necessary papers, but accidentally drops a locket with a photograph of his young wife Lucy.
The scientist Gustav Niemann admires the work of his colleague Victor Frankenstein and promises his cellmate, the hunchbacked Daniel, a new healthy body if they manage to leave the prison and find Frankenstein's manuscripts. Seizing the opportunity, they escape and immediately kill a passing Lumpini, who is driving around with his mobile "Room of Horrors". Blinded by a thirst for revenge, Niemann heads to the town where he was once sentenced to prison to not only exact revenge, but also to bring back to life the Werewolf Man and Frankenstein's monster buried beneath the ruins of the laboratory....
Wilbur and Chick transport two large boxes to a horror museum, one containing the body of Dracula and the other the body of a monster created by Dr. Frankenstein. The men decide to resurrect the two monsters, but the Wolf Man, the couple's eternal enemy, decides to stop them.
