Miley Cyrus has been cast in Dolly Parton's upcoming movie "Mountain Magic Christmas," joining her godmother, Dolly Parton, on the small screen this holiday season. The film, described as a modern-day movie musical, follows Dolly's journey to uplift the spirits of an exhausted world through a network TV special. Miley's dad, Billy Ray Cyrus, Jimmy Fallon, and Willy Nelson are also set to appear. The premiere date is yet to be announced. Dolly and Miley have collaborated in the past, and Dolly recently announced a deluxe version of her Christmas album.