Das dunkle Schloß (1915)

One day, the owner of the dark castle featured in the title, a certain Colonel Warringer, is found murdered. When the police arrive, they find the castle dog tied up outside the room. Beside the victim lies a hairpin, quite obviously belonging to the murderer—who, it is surmised, must be a woman. When the famous master detective Braun rushes to the scene, he is horrified to discover a portrait of his fiancée, Else Schmidt, on the murdered man’s desk. According to the servant, she was the last person to visit the colonel and thus the last to see him alive. The police’s suspicions therefore quickly fall on Else. But Braun distrusts the butler’s statements and investigates. And indeed, it turns out that the man lied. He wanted to shift suspicion from himself onto the young woman, because, in reality, as usual, the butler is the murderer.