Summary: An old priest intones "the curse of Amon-Ra, king of all the gods." Andoheb visits this dying high priest in a mountain temple (after some sand close-ups, set in what is clearly California -- that inescapable Little House on the Prairie topography). The old priest "shall not see the moon sink beneath the valley of the jackals again," so the new high priest is shown clips from the 1932 movie The Mummy with new names for the characters (Princess Ananka and Prince Kharis) and the Karloff close-ups replaced. 3000+ years ago, the princess died and Kharis stole sacred tana leaves to revive her but was caught. His tongue was ripped out so that the "gods would not be assailed by his unholy curses" and he was buried wrapped and alive with the supply of tana leaves. The slaves were killed so that the location of the tomb would remain a secret. Nevertheless, the priests pointlessly moved his tomb to a cave in the mountain as a guard appointed by Amon-Ra against defilers of Ananka's own tomb in the Valley of the Seven Jackals (a Universal budgetary and set availability decision on the part of the ancient priests). The old High Priest of Karnak, who is intended to be palsied but seems to have St. Vitus' Dance, offers the new guy the tana leaf recipes: "Three of the leaves . . . make enough fluid to keep Kharis' heart beating, one each night during the cycle of the full moon. You will dissolve three tana leaves and give the fluid to Kharis." We have a brief "Children of the night" moment when a jackal howls. Oh, and also, "nine leaves each night to give life and movement to Kharis; thus you will enable him to bring vengeance on the heads of those who try to enter." More than that and "he would become an uncontrollable monster, a soulless demon with a desire to kill and kill." A quick swearing by Amon-Ra, and the old priest kicks off.

Two American boneheads, lummox Steve Banning, fired from the Scripps Museum, and the Brooklynese Babe Jenson, buy a broken vase at the Cairo bazaar and bring it to the Cairo Museum where Dr. Petrie reads it like a map. But the real expert, Professor Andoheb (!), declares it a fraud and "accidentally" breaks it. Still, they plan an expedition with money fronted by a kindly magician, Solvani (actually Tim Sullivan, also from Brooklyn), whom they meet at a bar. A beggar in the employ of Andoheb tips off the boss and a brawl breaks out in the bar while Andoheb meanwhile tips off Solvani's daughter Marta about archaeological scams. Solvani presents her with a May 12, 1940 contract, but she totes a gun and seeks to retrieve his $2000. Nevertheless, she is won over by the sincerity of the Americans.

The expedition uncovers bones of a Gustavson and wife from previous expedition. TNT blasts a hole in the mountain, revealing an "unholy tomb" and a curse. What Banning openly calls a "silly native superstition" drives off the workers. A mummy is revealed in the unsealed tomb, but it's a male one, and "Where's the treasure: the gold and jewels?" Under a full moon, Dr. Petrie decides this mummy was buried alive, yammers about tana being "absolutely extinct now," that this mummy is Kharis, and that his skin is like "living tissue." Andoheb shows up saying, "There are some things in science which should be brought to light; there are others that should be left alone." He trickles tana juice on the mummy's mouth, Petrie notices the mummy's pulse quickening, and while he screams "Let me go!" Petrie is killed by the mummy. Andoheb declares that not one who entered the tomb shall remain alive. The natives are blamed for the death.

Andoheb instructs the mummy to kill wherever there's tana fluid to restore use of an awkward arm and leg. The beggar plants tana in a tent so that the last native on the dig, Ali, is killed. Another tana planting nearly results in Solvani's death, but the mummy kidnaps Marta. Steve shoots the beggar and discovers an amulet with the map that was on the vase earlier. He theorizes that there's a passageway, and he and Babe split up.

Andoheb has Marta tied up. He tells the mummy, "Your power to move wanes with the moon," and spills a rather sudden plan to immortalize Marta as his high priestess by injecting her with mulled tana in a syringe. When faced with the prospect of immortality, Marta unthinkingly cries, "No, no!" She suggests that Babe will shoot him, but Andoheb threatens that if he dies and Kharis gets hold of tana juice, "he will become a monster such as the world has never known" (unlike what he is?). Babe finds the temple and does shoot Andoheb, several times, who additionally rolls down the stone staircase outside the temple. Steve has found a secret passageway behind the mummy's case and arrives to get konked by the mummy who is going after more tana broth. Just in time, Babe shoots the bowl from the mummy's hand. The mummy stoops to lick tana spillage from the pavement and Steve smashes a brazier to set the mummy and the tana on fire. Marta and Babe pass out.