Werewolf of London (1935) on Netflix

After botanist Wilfred Glendon travels to Tibet in search of a rare flower, the Mariphasa, he returns to a London haunted by murders that can only be the work of bloodthirsty werewolves.

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.

—Jeremy Lunt <durlinlunt@acadia.net>

Dr. Wilfred Glendon returns to London with a rare flower he sought and discovered in Tibet. He also returns with the bite of a werewolf, which causes him to change into one himself during a full moon. Only the juice from his new flower can provide a temporary antidote. But the disease puts a strain on his relationship with his wife; worse, she's still in love with her old beau. Meanwhile, the flower has attracted the attention of the mysterious Dr. Yogami from Tibet.

—J. Spurlin

The British botanist Wilfred Glendon goes in an expedition to Tibet to search for the rare phosphorescent wolf-flower, the Mariphasa, that is located in a cursed place. While collecting the flower, Glendon is bitten by a strange creature. He returns to London and makes research with the flower. During an exposition, the mysterious Dr. Yogami tells him that there are two werewolves in London and the flower is an antidote to the lycanthropy that avoids the transformation into werewolf. Further the creature would seek out his love to kill. Glendon discovers that he has contracted the disease and when he seeks his flowers in the full moon, he finds that someone has stolen them from his laboratory. Now Glendon wants to protect his beloved wife Lisa from himself, but he begins a murder wave in London.

—Claudio Carvalho, Rio de Janeiro, Brazil