Released 13 May 1935, Werewolf of London was the very first well-known werewolf film. The film widely considered the first werewolf film, the 1913 short The Werewolf, was sadly lost in a 1924 fire at Universal Studios. The earliest surviving werewolf film, 1925’s Wolf Blood, takes forever to broach the idea of a man transmogrifying into a wolf, and shows no transformation at all. The filmmaking is also said to be awful even in the context of that era.
Though probably all classic horror fans consider Lon Chaney, Jr., the quintessential werewolf, Henry Hull does a solid job here. However, unlike Chaney’s Larry Talbot, the character here doesn’t evoke much sympathy or human warmth. It’s not hard to understand why his wife feels emotionally neglected.
Makeup artist Jack Pierce’s original look was identical to that of the later Wolf Man films, but TPTB vetoed it. They thought a simpler style would do a better job of making the werewolf’s true identity obvious to other characters.
Rich English botanist Dr. Wilfred Glendon (Henry Hull) travels to Tibet in search of the rare mariphasa flower, which is said to be the cure for lycanthropism and only blooms under the light of a full Moon. Despite being warned against this mission by a fellow Englishman (who’s been there for at least 40 years), he persists.
Wilfred and his assistant experience phantom pains and weird bodily movements as they make their way to the reportedly cursed valley where this flower is located, yet keep pressing on.
A werewolf attacks Wilfred just as he’s about to get the flower, leaving a long double-scratch on his arm and drawing blood. Wilfred, devoted to his mission, fights off the assailant and takes the flower.
Back in London, Wilfred throws himself into full-time experimenting and refuses to let anyone into his lab. This naturally makes his young wife Lisa (Valerie Hobson) feel quite neglected, and she begins spending a lot of time with her childhood friend Paul Ames (Lester Matthews).
Wilfred makes the reacquaintance of Dr. Yogami (Warner Oland), whom he very briefly met in the dark in Tibet. Dr. Yogami too is searching for the elusive mariphasa, for the same reasons, and asks Wilfred if his mission were successful. Though Dr. Yogami managed to get the flower, it died en route back to England.
Dr. Yogami says one bitten by a werewolf will also become a werewolf. Wilfred thinks this is a bunch of unscientific nonsense, but Dr. Yogami says there are two current cases of lycanthropism in London.
In the course of his research, Wilfred discovers he has indeed become a werewolf. Hair appears on his hands under the light of his lamp replicating moonbeams, which he’s using to try to make the flower bloom.
The mariphasa proves itself a successful antidote.
Dr. Yogami gets into the lab to speak with Wilfred again, and says this flower isn’t a cure, but just an antidote lasting a few hours. He also says a werewolf “instinctively seeks to kill the thing it loves best.”
In his house, Wilfred reads an old book which says a werewolf must kill at least one thing during a full Moon, or else become permanently affected. Lisa and Paul barge in while he’s reading, inviting him to a party. Wilfred refuses, and becomes very agitated when they turn on the lights. He claims he put medicine in his eyes and that light is very painful.
After they leave, Wilfred’s cat goes nuts, yowling, arching its back, hissing, and clawing at him. Wilfred looks at his hands and discovers he’s turning into a werewolf. Full of horror, he hurries towards the lab, only to find the mariphasa not blooming.
A strange howling fills the air, which piques the interest of everyone at the party. Lisa’s aunt Ettie (Spring Byington) reacts with laughter and odd comments. Out of concern, she’s taken up to her room, where Wilfred attacks her.
When Lisa and Paul come to investigate her screams, they find her alone and believe she had a nightmare or drank too much.
Wilfred then murders a woman in Goose Lane. This makes headline news, and an investigation is launched.
The mariphasa still refuses to bloom, and a full Moon is coming up. Wilfred begs off going riding with Lisa and Paul, and forbids Lisa to go. When he relents, he asks Lisa to promise she’ll be home before the Moon rises. This too is met with outrage, and Lisa stalks off with Paul.
Wilfred goes to rent a room out of town, hoping he’ll stay safely confined there and not turn into a werewolf. If he transforms anyway, he prays to be kept away from Lisa.
Since sometimes the answer to a prayer is “no,” Wilfred becomes a werewolf and jumps out of the locked window. The older women running this boardinghouse, Mrs. Whack and Mrs. Moncaster (Ethel Griffies and Zeffie Tilbury), provide great comic relief every time they’re onscreen.
Now the race to find the antidote and stay confined is on, before Wilfred can transform again and attack the one he loves most.