The Minus Man (1999)

Vann is a thoughtful and sympathetic man...and a serial killer. He doesn't kill for kicks, but thinks about the significance of his actions, how he upends people's lives, and what power he has. He takes a room in a small town with Doug and Jane, an unhappy couple who come to see him as a son. As he starts to have blackouts, his future as a serial killer looks uncertain - but will his past catch up with him?