Ratchet (1996)

Having missed several deadlines, and with the studio's attorneys hassling him, screenwriter Elliot Callahan (Tom Gilroy) takes the advice of his agent and rents a beachside house on the island Nantucket to find the peace and quiet he needs to get the creative juices flowing. There he meets the seriously intense Henry Carver (Matthew Dixon), who's written a screenplay he wants Callahan to read. Before long, Callahan suspects that Henry might be a serial killer writing about himself and that his screenplay is worth plagiarizing.

Unfortunately the movie Ratchet is not yet available on HBO Max.