Darby O'Gill and the Little People
King Brian lives in the Fairy Mountain, under the ruins of Knocknasheega, where he guards all of the greatest treasures of Irish history and myth. He has enjoyed a long-running rivalry/friendship with Rathcullen's local storyteller, Darby O'Gill. The two frequently try to outwit each other as Darby tries to win the crock of gold from Brian. His closest attempt was foiled when Brian tricked him into wishing a fourth wish, which undid the first three. But King Brian has a special fondness and respect for Darby due to their long history of outwitting each other.
When he learned Darby was being forced to retire, Brian brought him to his kingdom to stay, believing he was taking him out of his trouble. But Darby wanted to go back home to his daughter and tricked Brian by playing a tune on a violin that inspired the Leprechauns to go on a fox hunt. While they were distracted, Darby escaped the mountain. Later, Brian angrily came to Darby's house to take him back. Darby tricked him again by plying him with whiskey and singing a drinking song, keeping him until morning when his powers were gone. Powerless, he was forced to grant Darby three wishes. Darby's first wish was for Brian to stay by his side until he made the next two. As a further indignity, Brian was forced to be carried in a sack wherever Darby went.
When Darby attempted to show Brian to Michael MacBride, the leprechaun king disguised himself as a rabbit, making it appear that Darby was poaching. When Darby casually told Michael 'I wish you could see him,' Brian called out "Granted!" tricking Darby out of another wish.
When Darby admitted he could not think of another wish, Brian offered to do it for him and make his daughter, Katie fall in love with Michael. Brian visits both of them in their dreams to encourage their love. The next day, before Darby can make his last with, Katie bursts in and causes the sack to fall over. Brian escapes in the form of a rabbit.
That night, after suffering a dangerous fall, Katie was injured to the point of death, and the Banshee summoned the coiste-bodhar, a spiritual coach driven by the dullahan to carry her soul to the Otherworld. Darby summoned King Brian and sacrificed himself for Katie by making his third wish to go to Katie's place and Brian granted it.
As a final gesture of friendship, Brian offers to ride part of the way with his friend. To save Darby, Brian tricks him into making a final fourth wish ("wishing" that his friend could join him in the afterlife). As before, this fourth wish negates all the previous wishes and spares Darby's life. Darby is saved and King Brian has the last laugh in their running battle of wits. Presumably, since Brian is immortal, he can survive the trip to the Otherworld.
In this Walt Disney anthology series episode created to promote the film, Walt Disney goes to Ireland to research the folklore and recruits Darby O'Gill and King Brian to appear as themselves in the movie.
In a segment exploring the various supernatural characters in the story, King Brian and his leprechauns are described as having once been angels that hid away during the war between the Angel Gabriel and Satan, believing themselves too small to be of any help to Gabriel's army. As punishment for their cowardice, they were cast down to Earth and settled in Ireland, which they saw as the most heavenly place on Earth.
- Jimmy O'Dea was uncredited in the film because Walt Disney hoped to create the illusion that he was using real leprechauns. He even filmed a TV spot of himself asking King Brian to appear in the film, and included an insert to the opening credits thanking King Brian and his leprechauns for their 'cooperation.' Disney even went so far as to film the Walt Disney's Wonderful World of Color (1954) episode, "I Captured the King of the Leprechauns" (#5.26), in which he and "Darby" (Albert Sharpe) manage to corner King Brian and convince him to participate in the film along with his people.
- Jimmy O'Dea was the most well-known comedian in Dublin from the 1930s until his death in 1965. He starred in several films, but those who knew him said that of all the roles he played on screen, King Brian was the closest representation of Jimmy's own personality.
- Jimmy O'Dea preferred stage performances to the big screen, using his platform to satirize the class system in Dublin and poke fun at the rich, while turning the working class into sympathetic comedic characters, earning him comparison with Charlie Chaplin.
- When Michael doesn't kiss Katie, King Brian (Jimmy O'Dea) exclaims "And him a Dublin man!" O'Dea was born and raised in Dublin.