In “The Hidden Fortress”, which Star Wars plot and characters (minus Luke) is mostly based on, “Obi Wan” humiliates “Darth Vader” by refusing to kill him after

In “The Hidden Fortress”, which Star Wars plot and characters (minus Luke) is mostly based on, “Obi Wan” humiliates “Darth Vader” by refusing to kill him after beating him in their duel. The Emperor horribly tortures Darth Vader for losing, which convinces him to switch sides and help Obi Wan and the princess escape, and the ending is the three of them rejoining the rebellion, ready to fight another day.