Werewolf of London

Botanist Dr Wilfred Glendon goes on an expedition into the Himalayas in search of the marifisa lupina lumina, a rare orchid that only blooms by moonlight. He finds the marifisa in a remote valley but is attacked and his arm gored by a wolf creature. Back in England he meets Dr Yogami who implores him to give the marifisa clipping, the only known cure for lycanthropy, to him. And then as the moon rises, Glendon finds himself turning into a werewolf creature, rampaging through the streets of London and driven to attack people.