After a broadcast from his radio station in a small Connecticut town, Hank Martin, a supplier of radio equipment, makes a delivery during a severe thunderstorm because his assistant says that the destination, an old mansion, is too spooky. Upon arriving, Hank is confronted by a girl, who beseeches his help to get away, and by a young man, hiding in a suit of armor, who says he is the girl’s friend. A seductive woman then warns Hank not to protect the girl. The master of the house has Hank hook up a battery to an invention, which, the man hopes, will enable him to hear sounds from the past that are still vibrating in the ether. When a voice announces that it is from the court of King Arthur, Hank, frightened, tries to leave, but a door knocks a suit of armor on top of him. He awakens in another time period as a knight, Sir Sagramor, prods him with a lance. When Sagramor takes him to Camelot Castle and brags that he has captured a demon, Hank, to save his life, proves that he has magical powers by lighting his cigarette lighter. King Arthur’s magician Merlin, who is envious that he can’t make the lighter work, convinces the king to burn Hank at the stake. When Hank notices in his pocket notebook that a total eclipse of the sun occurred at noon on June 21, 528 A.D. and learns from another prisoner, Emile le Poulet, whom he dubs Clarence, that today is the 20th of that year, he threatens to blot out the sun the next day unless he is released. Goaded by Merlin, the king moves the execution time to the immediate present, but Hank then learns that today is actually the 21st and revises his threat. The subsequent eclipse causes the king to beg for the sun’s restoration. Hank obliges and then agrees to be the king’s prime minister. The “magical” changes instituted under Hank include telephones, messengers on roller skates, factories to produce things people have been happy without, and advertising to make them want those things. When Queen Morgan le Fay, the king’s sister, sends word that unless Arthur gives her half his kingdom, she will put his daughter, Princess Alisande, on a torture rack, King Arthur decides that Hank and Sagramor shall joust for the honor to save Alisande. In his cowboy outfit, Hank easily wins by lassoing Sagramor and dragging him around the arena, but he suggests that Clarence, who loves the princess, rescue her instead. Because Clarence is only a page, and therefore cannot marry a princess, the king dubs him Sir Rogers de Claremore, which, it turns out, is the name of Hank’s ancestor, whom he has been trying to locate. Afraid that if Clarence dies, he himself will never be born, Hank offers to save Alisande himself and convinces King Arthur to go with him. Merlin, who is friendly with the queen, and Sagramor plot against them, and after Sagramor’s men capture Arthur and Hank, and strip Arthur of his beard, Queen Morgan refuses to recognize him. Attracted to Hank, the queen attempts to seduce him. He escapes her grasps and releases Arthur and Alisande from a torture chamber, but they are recaptured and taken to the gallows. As King Arthur is about to be hanged, Clarence, in a helicopter, drops a bomb, and tanks and armored cars equipped with machine guns arrive to do battle. Hank releases the torture victims, but he is then surrounded by the queen’s forces. A dynamite explosion knocks him out, and he awakens in the mansion of the inventor just as a radio broadcast of the “Knights of the Round Table” ends. The inventor, whom Hank had imagined as King Arthur, is chagrined because he mistook the voices from the radio show for those of the real historical characters. As Hank quickly leaves, he discovers the girl and boy he met earlier, who resemble Alisande and Clarence, inside his truck. They tell him that the inventor is the girl’s father and that her aunt, the seductive woman, who resembles Queen Morgan le Fay, does not want the girl to marry the boy. Hank gives them the truck to go to a minister and walks home in the storm. More on Wikipedia
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