The Phantom Creeps (1939)

This 1939 sci-fi serial, directed by Ford Beebe and Saul A. Goodkind, follows the nefarious Dr. Zorka, portrayed by Bela Lugosi, a mad scientist who possesses a deadly meteorite element called 'meteorium.' Zorka plans to create destructive weapons and conquer the world, facing off against government agents and a journalist, while also dealing with his own creations: an eight-foot-tall robot named the 'Iron Man' and other bizarre inventions.