In 1921, an archaeological expedition led by Sir Joseph Whemple (Arthur Byron) finds the mummy of an ancient Egyptian high priest named Imhotep (Boris Karloff). An inspection of the mummy by Whemple's friend Dr. Muller (Edward Van Sloan) reveals that the viscera were not removed, and from the signs of struggling Muller deduces that although Imhotep had been wrapped like a traditional mummy, he had been buried alive. Also buried with Imhotep is a casket with a curse on it. Despite Muller's warning, Sir Joseph's assistant Ralph Norton (Bramwell Fletcher) opens it and finds an ancient life-giving scroll, the "Scroll of Thoth". He translates the symbols and then reads the words aloud. Imhotep rises, the sight of which snaps Norton's mind and causes him to laugh hysterically, as the Mummy shuffles off with the scroll.