"She-Wolf of London" is an okay film for what it is. I imagine that horror fans were disappointed, asking "Where's the Werewolf?" (Why Jack Pierce is credited as the makeup man in the opening credits I don't know, since I can't see any place in the film where his special makeup talents were employed.) The story: In Victorian London, a series of murders takes place in a public park, where the survivors report being attacked by a female werewolf. A young woman, Phyllis Allenby (June Lockhart), suspects that she might be a werewolf in question. Supposedly, it is a family curse, "the curse of the Allenbys." Phyllis wakes up in the morning to find blood on her clothes and dirt tracks on the floor of her bedroom.
More, I won't say, since it will spoil the mystery for those who haven't seen the movie.
"She-Wolf" is more of a Gothic thriller than a monster movie. It has elements of George Cukor's "Gaslight," and Hitchcock's "Rebecca" and "Suspicion." If they had spent a bit more exposition time on the plot, it might have been a classic thriller. Nevertheless, it still does okay as a nice, eerie, foggy-gaslit melodrama.