The Prisoner of Karlsten's Fortress

"The Prisoner of Karlsten's Fortress on xfmoviess.com " – Count de Faber is working on a new type of explosive, but finds out that Professor Plussman has beat him to it. After an unsuccessful attempt to acquire the formula from Plussman, he breaks into the professor's house, steals the formula, and kidnaps his daughter, Mary. He takes her to Carlsten Fortress.