Dr. Cameron has succeeded in his experiments with a serum which will turn a man into a wolf-like monster, and is ready to avenge himself on the men who caused his professional failure. He uses it on his gardener Petro and one after the other is killed by his creation. His daughter, Lenora, grows suspicious and confides with newspaper reporter Tom Gregory.
The Mad Monster
A mad scientist changes his simple-minded handyman into a werewolf in order to prove his supposedly crazy scientific theories - and exact revenge.