In an episode titled "The Secret Library: Olaf and the Tale of Miss Nettle," premiering Feb. 15 at 11:30 AM ET on Disney Channel, the role of Miss Nettle will be voiced by Golden Globe nominee and Broadway vet Mullally (Young Frankenstein), with "Modern Family"'s Ariel Winter in the lead role of Sofia and Gad (The Book of Mormon) reprising his role as Olaf the Snowman. The children's series follows the life of a little girl who is suddenly made into a princess when her mother marries a king.

In the episode, according to production notes, "Sofia sets out on a mission to stop Miss Nettle from stealing all the beautiful snowdrop flowers from the wintery kingdom of Freezenberg, so the wicked fairy puts a curse on Sofia's amulet which ends up summoning Olaf (instead of a princess) to help her. In the end, Olaf helps Sofia learn that she doesn't need the powers of her amulet and can rely on her own bravery and resourcefulness to save the day."

The guest voice cast includes Gad as Olaf; Mullally as Miss Nettle; Eric Stonestreet as Sofia's horse, Minimus; and Hugh Bonneville as the Narrator.

Watch an exclusive clip here:

Gad's character of Olaf was recently seen in the Walt Disney Animation Studios' short film "Frozen Fever," which made its television debut on the Disney Channel Nov. 29, 2015.

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