Adventures of Sir Galahad (1949) was a 15-chapter Columbia Pictures film serial based on Arthurian legend. It was one of the very few serials of the time with a period setting that was not a western. It was Columbia's forty-first serial (of the fifty-seven they produced between 1937 and 1956).

Galahad is played by George Reeves, who would later find stardom as Superman in The Adventures of Superman. The serial was directed by experienced serial director Spencer Gordon Bennet and produced by legendary cheapskate Sam Katzman.

Sir Galahad is refused admission to King Arthur's Round Table until he regains the missing magic sword "Excalibur," which makes its possessor invincible. Ulric, the Saxon King, invades England. Galahad, aided by Sir Bors, attempts to retrieve "Excalibur" from Bartog, Ulric's chief aide, who has gotten it from a mysterious Knight.Merlin the Magician harasses Galahad at every turn, while Morgan le Fey, Arthur's sister and also a magician, helps Galahad fight both Merlin's magic and the Saxons. The Black Knight, a traitor within Camelot, is conspiring with the Saxons and a band of outlaws to overthrow King Arthur. When Queen Guinevere is seized by the traitors, Merlin relents and sends Galahad to the Lady of the Lake, who gives him "Excalibur." Written by Les Adams