"Even a man who is pure in heart and says his prayers by night, may become a wolf when the wolfbane blooms and the autumn moon is bright."
Dec 12, 1941 - Lawrence Stewart "Larry" Talbot (Chaney) returns to his ancestral home in Llanwelly, Wales to reconcile with his father, Sir John Talbot (Rains). While there, Larry becomes romantically interested in a local girl named Gwen Conliffe (Ankers). On a night of the full moon (which, oddly, is never seen in the film), he attempts to rescue her friend Jenny from what he believes to be a sudden attack by a wolf. He kills the beast with a silver-headed walking stick, but is bitten in the process. He soon discovers that it was not just a wolf; it was a werewolf, and now Talbot has become one. A Roma fortuneteller named Maleva (Ouspenskaya) reveals to Larry that the animal which bit him was actually her son Bela (Lugosi) in the form of a wolf. Bela had been a werewolf for years and now the curse of lycanthropy has been passed to Larry. Throughout the film, Larry is told by Gwen, Jenny, and his father:
"Even a man who is pure in heart/and says his prayers by night/may become a wolf when the wolfbane blooms/and the Autumn moon is bright."
Sure enough, Talbot prowls the countryside in the form of a two-legged wolf. Struggling to overcome the curse, he is finally bludgeoned to death by his father with his own walking stick. As he dies, he returns to human form.
A werewolf (or lycanthrope) in folklore and mythology is a person who shapeshifts into a wolf, either purposely, by using magic, or after being placed under a curse. The medieval chronicler Gervase of Tilbury associated the transformation with the appearance of the full moon, but this concept was rarely associated with the werewolf until the idea was picked up by modern fiction writers. Most modern references agree that a werewolf can be killed if shot by a silver bullet, although this is more a reflection of fiction's influence than an authentic feature of the folk legends. A werewolf can be killed by complete destruction of heart or brain; silver isn't necessary. Werewolves are sometimes held to become vampires after death.