In the werewolf scene, when the hunters arrive to kill the werewolf, the young one hands the older one a box containing 3 silver bullets. The older hunter drops the bullets and as he is bending down, we see all 3 on the ground. A few minutes later the older hunter loads a silver bullet and shoots the werewolf. We then see Tony beginning to change. The older hunter kneels down to get another bullet and we see 3 intact bullets on the ground.
Near the beginning of the movie, James and Gemma chicken out of attending the Waxwork tour with their friends and are not mentioned to the staff inside. However, near the end of the film, the butler Junior calls James and tells him to arrive at the Waxwork with Gemma at midnight to meet their friends Mark and Sarah.
When China enters Dracula's dining room, from the front Dracula is sitting at the dining table. When it cuts to a back view on Dracula, however, he's standing instead. In the following side shot, Dracula is seated and then he stands up.
When Sarah is in Mark's attic, she looks at a book of the Marquis de Sade in a trunk and it glows with white light. When Sarah looks up, hypnotized by the book when it glows, her left hand runs up to the top of her dress. However, in the very next shot, Sarah's left hand is suddenly down and it runs up to the top of her dress all over again.
When Mark walks with Sarah to leave the Prince's Chamber to go into the hall, the back of a set and a camera cable on the floor are seen instead through the doorway when they pass through the curtains.
In an early scene, while a professor lectures about the Lithuanians falling to the Nazis, a phrase on the blackboard, very clearly seen, asks, "Facism Does It Work" It is spelled f-a-s-c-i-s-m. One wouldn't expect a college professor, who specializes in the subject, to make the common spelling error.
In the vampire scene, Chyna is in the kitchen with what's supposed to be her fiancé. The fiancé is strapped to the butcher's block with his left leg stripped of flesh and muscle from the knee down so there's nothing but bone. A rat is scene gnawing on the bone causing him pain. Trouble is, all the nerves were stripped away so he shouldn't have been feeling pain.
The goof items below may give away important plot points.
When one of Sir Wilfred's slayers is being strangled by Jack the Ripper, he is shouting for Sarah to help him and stab the Ripper. Look closely at the background when you see Sarah, and you can see Jenkins is strangling and kills the Maid from the Demonic Baby display. A few minutes later, when Sir Wilfred's slayers are seen fighting with the Waxwork displays that have come to life, the Maid is alive and attacking the hunters.
After Sarah has thrown the Lumberjack's ax and hits the Marquis de Sade in the back, the Marquis falls dead and lands back-first against the bricks surrounding the large vat of boiling wax. However, the brick wall visibly wobbles and shakes when the Marquis collides onto it.
In the shot of Sir Wilfred being attacked and decapitated by a werewolf, you see the werewolf tear his head off his shoulders. However, in the next shot of Sir Wilfred's body, you can clearly see the actor's head, tilted back to make it appear as though the body is headless.