Continuity mistake: Houdini's grey on his temples changes dramatically between shots. For example, when he finally goes to Von Schweger's home, when he knocks on the door his temples are mostly white. Then when he enters the home, he has almost no white on his temples. Then in the following scene his temples are mostly white again.
Continuity mistake: Just after Houdini returns to the United States from his European tour, he stages a publicity stunt. The lady in the apartment opens her window shade and sees Houdini hanging upside down, directly outside the window. When it cuts to an outside shot, he is now suspended above the roof line, where the woman would not be able to see him.