In GASLIGHT, Paula Alquist (Ingrid Bergman) falls in love with Gregory Anton (Charles Boyer), a musician, and once they are married, he persuades her to move into the house she lived in as a child, which has been closed since her aunt was murdered there. Gregory seems solicitous and caring, but he isolates Paula from everyone and makes her doubt herself and her sanity. He convinces her that she is always losing things, that she sees things that are not there, that she is unstable and untrustworthy. Every night, while Gregory is away, the gaslights flicker and Paula hears noises from the attic. Gregory persuades her that these are just her delusions. Just as Paula's fragile hold on reality is about to break, she is visited by Brian Cameron (Joseph Cotten) of Scotland Yard. With his help, she learns that Gregory is using an assumed name, that he is a thief, and that he had known her late aunt, a famous singer, and Cameron and Paula team up to stop Gregory from pulling off his devious plan.