"Gaslight" (GB 1940)
I am referring to the first movie from 1940 but not the U.S. remake four years later.
Gaslight (1940 film) - Wikipedia
1880s London. Louis Bauer (Anton Walbrook), who has murdered his aunt to steal her rubies didn't find them. The police could not catch him. Years later he had changed his name to Paul Mallen and married Bella (Diana Wynyard), a mental fragile women. With her he returns to the house to search for the rubies again. Every time Paul lights the gas lamps to search the closed-off upper floors, which causes the rest of the lamps in the house to dim slightly. When Bella comments on the lights' dimming, he tells her that she is imagining things. Bella is persuaded that she is hearing noises, unaware that Paul enters the upper floors from the house next door.
This is even part of a plan to drive Bella mad. But B. G. Rough (Frank Pettingell), a former detective involved in the original murder investigation, begins to suspect Paul of Alice Barlow's murder.
There is the original black and white movie on YouTube, but I like the colored version more, since in my opinion it provides a more sinister atmosphere.
Katie Feldman (Julianne Hough) moves to a small town on the North Carolina coast, determined to make a new life for herself. She takes a job as a waitress and keeps a low profile, but she is soon won over by the warmth and caring of the close-knit community, especially that of widower Alex (Josh Duhamel). With the help of Alex and his children, Katie learns to love and trust again -- but when a mysterious stranger arrives and starts asking questions Katie's dark past is brought into question.
