A demented archaeologist discovers a living, breathing serpent creature known to the Aztecs as Quetzalcoatl and accidentally kills his wife by giving her one of the beast's feathers, causing the creature to track her down and slaughter her. Using this knowledge he exacts revenge upon his enemies by placing one of the feathers on his intended victim and letting the beast loose to wreak havoc.

When a small town doctor buries his twin brother, a practitioner of the black arts, he believes him dead; but subsequent events force him to realize that his brother has, in fact, returned from the dead as a vampire and is seeking revenge on the doctor, who had killed him in self-defense.

A university chemistry professor experiments with an ancient Mayan gas on a medical student, turning the would-be surgeon into a murdering ghoul as part of a plan to steal his lover.

A mad scientist changes his simple-minded handyman into a werewolf in order to prove his supposedly crazy scientific theories - and exact revenge.

A mad doctor (Bela Lugosi) and his helpers (John Carradine, George Zucco) lure girls to his lab for brain work, to help his wife.

拉里·海恩斯，一个平庸的杂耍艺人，登上了开往洛杉矶的火车。在船上，他遇到了一位迷人的金发英国特工，胸针里藏着一条密码信息，正被纳粹特工追捕。

An ordinary man, while vigorously asserting the impossibility of miracles, suddenly discovers that he can perform them.

A woman is married to the son of a doctor, the proprietor of a private sanatorium, where she is under unwilling treatment. Both the son and the doctor indicate they want the marriage dissolved. Arriving at the scene is a mysterious personage identified as the doctor's cousin who formerly was a stage magician in Europe. He is accompanied by a threatening dwarf.