Copenhagen's sherlock holmes (1925)

Karen Wang and her beloved Kai Ørn live happily together. However, just as he’s about to propose, a serpent slithers into the paradise: Viggo Eibye, who’s a bad man, also wants to marry Karen. For financial reasons, she says yes to the marriage, but before the wedding day, Viggo Eibye dies in mysterious circumstances. Wang and Ørn are suspected, and two men are put on the case – the brusque detective Engberg and a cunning reporter, who may be able to explain how these cases are actually intertwined. (stumfilm.dk)