Bad Moon (1996)

Synopsis:
While on an expedition in Nepal, a photo-journalist (Michael Paré) and his girlfriend are attacked by a werewolf that kills her and savagely bites him. The researcher moves back to the Pacific Northwest to live in isolation with his lycanthropy until his well-intentioned sister (Mariel Hemingway) invites him to stay with her and her son (Mason Gamble) to get over the grief of losing his lover. Things soon begin to go bad, especially when the family dog, a big German Shepherd named Thor, just can't accept the werewolf among them.
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