A renowned British doctor (Ronald Lewis) is summoned to a castle in Central Europe by his ex-girlfriend (Audrey Dalton). She asks him to perform a miracle cure on her paralysed husband, Baron Sardonicus (Guy Rolfe). The treatment is a success, and as a reward the Baron clears the way for his wife to return to the doctor's arms. However, the castle's devious servant reverses the effect of the cure - and the Baron finds his jaws are jammed together.