I Bury the Living (1958)
Underrated horror noir from B-movie director Albert Band. Richard Boone gives a fantastic performance as the lead character who starts to question his own sanity after he discovers people die every time he puts a black pin in their grave site on the map in the cemetery office. I found it fascinating watching his decent into depression and madness. The use of lighting and score set the mood perfectly and the building tension throughout is superb. The reveal at the end was a bit predictable by today's standards but nonetheless effective and the ending is very satisfying. I'm already looking forward to rewatching this.