The fact that this is labeled as horror shouldn't discourage anyone; it’s not frightening, and doesn't try to be. Conrad Veidt gives a terrific performance as a magician who has strong feelings for his young assistant, Julie (Mary Philbin), and wants to marry her once she reaches an appropriate age. The problem is that those feelings aren’t returned. She’s occupied with rejecting the advances of his assistant Buffo (Leslie Fenton) and is actually in love with his apprentice Mark (Fred MacKaye, who looks quite handsome). This younger man isn't entirely trustworthy, something Erik, the magician, is aware of, and a basic principle of magic—or at least it should be—is to avoid provoking someone who’s passionately in love, especially when they are about to be placed inside a box for the sword trick. We can probably anticipate much of what follows, although there are some unexpected developments during the courtroom scenes that maintain our interest. The film is visually appealing, and certain illusions are genuinely perplexing. I found the romantic complications a little over-the-top, but Veidt’s presence ensures the movie remains engaging, and I ended up enjoying it quite a bit.

Source on TMDB