Megalomaniac and would-be world dominator Roxor has kidnaped Robert Regent, along with his death ray invention, in hopes of using it to degenerate humanity into mindless brutes, leaving himself as Earth's supreme intelligence. Faced with revealing the machine's secrets or allowing his family to die a horrible death at the hands of Roxor, Regent's only hope lies with the intervention of his brother-in-law, the be-turbaned yogi and magician Chandu, who has the power to make men see what is not there 'even unto a gathering of twelve times twelve'
In 1921 a field expedition in Egypt discovers the mummy of ancient Egyptian prince Im-Ho-Tep, who was condemned and buried alive for sacrilege. Also found in the tomb is the Scroll of Thoth, which can bring the dead back to life. One night a young member of the expedition reads the Scroll out loud, and then goes insane, realizing that he has brought Im-Ho-Tep back to life. Ten years later, disguised as a modern Egyptian, the mummy attempts to reunite with his lost love, an ancient princess who has been reincarnated into a beautiful young woman.
Divorced Ethnologist John Parker loves his two boys, Al and Terry, and misses them terribly when they have to leave his archaeological dig at the end of the summer. While Al goes to military school, Terry returns home and learns that his mother, Grace, has married Dr. Phil Shumaker, a stable man who can provide the home that Grace never had with John.