The Mummy's Curse is a 1944 American Universal Pictures horror film, directed by Leslie Goodwins. It is the third and final sequel to that company's The Mummy's Hand of 1940. The film is the sequel to The Mummy's Ghost (1944). The film is the fifth entry in Universal Pictures' original Mummy franchise. It marks Lon Chaney, Jr.'s final appearance as Kharis, the Egyptian mummy. The action of this film, which continues the story of Kharis and his beloved Princess Ananka, is supposed to take place in the same swampy location that was the setting of The Mummy's Ghost. But while the earlier movie was explicitly set in rural Massachusetts, this film strongly implies that the swamp is in Louisiana, with references to Cajuns and bayous. Furthermore, if one follows the continuity of the "Kharis" series, this film would have to take place in the late 1990s.
The Southern Engineering Company is trying to drain the local swamp for the public good. However, the efforts are being hampered by the superstitions of the workers, who believe the area to be haunted by the mummy and his bride.
Two representatives of the Scripps Museum, Dr. James Halsey (Dennis Moore) and Dr. Ilzor Zandaab (Peter Coe), arrive on the scene and present their credentials to the head of the project, Pat Walsh (Addison Richards). They have come to search for the missing mummies, buried in the swamp years earlier. Their conversation is interrupted by the news that a workman has been murdered in the swamps. Evidence at the scene convinces Halsey that the murderer has found the mummy of Kharis.
Later that evening, Zandaab sneaks into the swamp and meets Ragheb (Martin Kosleck). Ragheb is a disciple of the Arkam sect, and Zandaab is secretly a High Priest. The follower killed the worker that unearthed Kharis, and has taken the immobile monster to a deserted monastery.
Zandaab explains the legend of Kharis and Ananka to Ragheb as he brews the tana leaves, giving instructions on their use. The old sacristan of the monastery (William Farnum) intrudes on their ritual, and is promptly executed by a risen Kharis.
Meanwhile, the mummy of Ananka (Virginia Christine) rises from the swamp after being partially uncovered by a bulldozer during the excavation. She immerses herself in a pond and the mud is washed away, revealing an attractive young woman.
Cajun Joe (Kurt Katch) finds the girl wandering listlessly in the swamps, calling out the name "Kharis". He takes her to Tante Berthe (Ann Codee), the owner of the local pub, who aids the girl. Later, Kharis finds her there and murders Berthe, as Ananka flees into the night.
Ananka is soon found lying unconscious beside the road by Halsey and Betty Walsh (Kay Harding), the niece of Pat Walsh. While in their care, and although apparently suffering from amnesia, the girl displays an incredible knowledge of ancient Egypt. Her stay at Halsey's camp is again interrupted by the appearance of Kharis, and the kindly physician, Dr. Cooper (Holmes Herbert), is killed. She again takes flight, and Halsey and the others go in search of her.
Fleeing the monster after he attacks and kills Cajun Joe, she comes to Betty's tent seeking refuge. However, Kharis is not far behind. He enters the tent and whisks away his Princess, leaving the horrified Betty unhurt.
Betty asks Ragheb for his help in finding Dr. Halsey. The treacherous disciple has other ideas, and takes her to the monastery instead. Zandaab, having already administered the tana fluid to the young Ananka, is angered to find Ragheb making advances on Betty. He orders her death, but Ragheb kills him instead. Halsey arrives, tracking them from the camp after finding Betty's tent destroyed. A struggle ensues between Ragheb and Halsey, until Kharis intervenes. The creature, sensing Ragheb's betrayal, advances on his former ally.
Locking himself inside a cell-like room, Ragheb is powerless to do anything but watch as Kharis literally brings down the walls on the two of them. Halsey, Betty and the rest find the mummified remains of Ananka in the adjoining room.