The Sword in the Stone
The film is loosely based on the novel The Sword in the Stone, the first book of T.H. White’s tetralogy The Once and Future King. From Merlin’s statement that The Times won't come out for another 1200 years, it may be extrapolated that the film is set circa A.D. 600.
The Sword in the Stone follows the future King Arthur’s life during his education by the wizard Merlin. Arthur, called “Wart” by his family, is a 12-year-old orphan who lives with Sir Ector, his foster father, and Kay, his older foster brother. One day, as Wart searches the woods for a lost arrow, he meets the wizard Merlin and his talking pet owl Archimedes. Merlin sees great potential in the boy and commits himself to Arthur's education, which is to consist of reading, science, and magical transformations. Sir Ector, on the other hand, plans to teach Wart about fighting and chivalry to prepare him to be Kay’s squire.
For his first transformation lesson, Merlin turns Wart into a perch. In fish form, Wart is chased and attacked by a huge pike. He works to outsmart the beast but is nearly caught. Archimedes flies down and plucks Wart from the pike’s jaws, saving him, but the owl later denies any altruism, claiming instead that he merely had planned to eat what he thought was an ordinary fish.
For his second lesson, Merlin transforms Wart to a squirrel. Though Wart begins by learning about the principle of gravity, he ends up learning about male-female relationships when he runs into a female squirrel who becomes infatuated with him. Merlin is amused until another female squirrel finds him attractive as well, and the student and teacher are forced to fend off the amorous attentions of both females. After a wolf nearly eats Wart, Merlin transforms both of them back into humans. While Merlin’s squirrel companion is merely horrified, Wart’s companion is visibly heartbroken.
For his last lesson, Merlin transforms Wart to a bird. Merlin doesn’t join him; instead, Archimedes teaches Wart the principles of flight. Wart’s skill and enjoyment rapidly become apparent to Archimedes, but his daring forces him to flee from the pursuit of a hawk. During his escape, Wart is taken hostage by "The Marvelous Mad Madam Mim," a witch in competition with Merlin. She claims that her magic, which is based on selfishness and trickery, is more useful than Merlin's magic, which is "for educational purposes." After Merlin locates his hostage student, Merlin and Mim engage in a wizards' duel in which each seeks to defeat the other. As they transform into a series of creatures, it seems that Mim’s dragon form will win. However, Merlin transforms himself into a germ and infects her, leaving her bedridden and furious.
Later, Wart begins his service as squire to Kay. Merlin, disappointed that Wart still prefers war games to academics, transports himself to 20th-century Bermuda. Ector, Kay, and Wart travel to London for a Christmas tournament which will decide who will be the next King of England. As Kay’s turn to fight approaches, Wart realizes that he has forgotten Kay's sword at their inn. He tries to retrieve it, but the door is locked, and he frantically searches the town for another sword for Kay. He sees a sword protruding from an anvil on a stone in a churchyard, and pulls the sword from the stone, unwittingly fulfilling the sword’s prophecy and making himself king.
Though Sir Ector, Kay, and the other knights initially don’t believe Wart is the foreordained king, they are forced to accept him when it becomes clear after repeated tries by others that he alone can pull the sword from the stone. Arthur, feeling unprepared and apprehensive of his failure, calls to Merlin for help. After the wizard appears and the facts become apparent, Merlin is elated to find that Wart will be the King Arthur that he has seen in the future. Merlin tells Arthur that he will rise and lead an order of heroes, and reveals other anachronistic information.