A 1921 British field expedition to Egypt uncovers the mummy of Prince Imhotep, who was condemned and buried alive 3,700 years ago, along with the Scroll of Thoth, which can bring the dead back to life. When a young member of the expedition reads the Scroll out loud, Imhotep (Boris Karloff) is reawakened. Eleven years later, the ageless mummy, disguised as a modern Egyptian, attempts to reunite with his lost love, an ancient princess who has been reincarnated as a beautiful young woman (Zita Johann).