While on a botanical expedition in Tibet Dr. Wilfred Glendon is attacked in the dark by a strange animal. Returning to London, he finds himself turning nightly into a werewolf and terrorizing the city, with the only hope for curing his affliction a rare Asian flower, the Mariphasa. Starring Henry Hull, Warner Oland, and Valerie Hobson. The original werewolf movie. How did that song go?