In the late Eighteenth Century, a European town is under siege of the Turkish army. Meanwhile, the theater company owned by Henry Saltis entertains the dwellers with the production of "The Adventures of Baron Munchausen". Out of the blue, an old man interrupts the presentation claiming that he is Hieronymus Karl Frederick Baron von Munchausen and the tells that he is the one to be blamed by the Turkish attack. The Baron Munchausen tells how he had won a bet against the Sultan with the abilities of his servants Berthold; Adolphus; Albrecht; and Gustavus and earned his treasure. Further, he offers to help the locals against the Turks and builds a balloon to seek out his missing servants. During his journey, he finds the girl Sally hidden in the balloon and they travel to the moon, where they meet the deranged King of the Moon Roger with his detachable head, and his wife, the Queen of the Moon Ariadne that has a crush on the Baron. They are arrested by the jealous Roger and find Berthold in the cage, but Ariadne releases them. When they escape from the moon, they meet Adolphus working to Vulcan inside a volcano. The Baron Munchausen seduces the gorgeous Vulcan's wife Venus and the jealous god throws them in a whirlpool. They are swallowed by a monster and they meet Albrecht and Gustavus in a ship inside the monster. They escape and return to the town to help the people against the invaders. But they are very old and their abilities are gone.