When his girl-friend Doris disappears in mysterious circumstances from the forest clearing in which they have been dallying, Albert Potter reports the matter to Detective Sergeant Bung and his assistant, Slobotham. Investigating several similar disappearances, Bung and Slobotham find a house near the clearing, but are unsuspicious of its very suspect owners, Dr. Watt and his vampirish sister, Valeria. Dr. Watt, a corpse who revivifies himself with electrical charges, has a pet monster called Odbodd who goes out collecting girls; Watt and Valeria then vitrify them and sell them profitably as window-dummies. Bung is given a lead by Dan, a lavatory attendant, who is promptly drowned by Odbodd in one of his own toilets; investigating the lead, Bung is sidetracked into a hectic affair with Valeria. Eventually, using Slobotham in female disguise as a decoy, Bung precipitates a showdown; but not before his own shrewish wife, Emily, has been vitrified. Albert, under the accidental influence of a potion, destroys Odbodd and another monster who has been inadvertently created from Odbodd's severed finger; Watt is attacked by a mummy he has revivified, and both of them fall into the vitrifying vat; and Doris, de-vitrified, is reunited with Albert. Bung, preferring to leave his wife in her vitrified state, takes her home along with Valeria, who will minister to his needs.
Apart from an engaging performance by Jim Dale (and some appealing squeaks from monster Odbodd Junior, alias Billy Cornelius), this is glum stuff even by Carry On standards. The regulars, Kenneth Williams in particular, seem too bored to care; Harry H. Corbett overdoes every line; and the horror clichés are rather less amusing than the straight routines in some of Hammer's early epics.