Watch Online Free HD Solarmovies. "The Adventures of Sir Galahad" is the 41st serial released in 1949 by Columbia Pictures. It was was based on Arthurian myth and legend. Galahad is tasked with guarding Excalibur over night to prove he is worthy to become a Knight of the Round Table. When the sword is stolen, he must search the land to reclaim Excalibur and restore his owner.