This movie was surprisingly good – Fritz Lang allows a lot of the mystery to come from what you picture yourself. Joan Bennett, as “Celia,” finds herself drawn to Michael Redgrave’s character, "Mark," who's clearly hiding something about his family’s past. They go to live at his isolated family home where she encounters his sister and a teenage son she didn’t know existed. Odd occurrences begin almost immediately after her arrival; he has a habit of collecting rooms—recreating spaces where terrible things happened in the past. There's one room in particular that he keeps under lock and key, prompting curiosity about its contents. Her anxiety, heightened by some unsettling lighting and Redgrave’s subtly suspicious acting, steadily intensifies until it reaches a fairly gripping conclusion. It shares similarities with "Rebecca" (1940), where Anne Revere's character, “Caroline,” takes on the part of the secretive and fixated outsider, and there's enough uncertainty to maintain engagement throughout.

Source on TMDB