The enchanted Winged Ring which Queen Blossom gave to Geronimo is missing, apparently stolen by the dark fairy Wither and her dark crow allies, and whoever possesses it gains enormous power and can travel between the Kingdom of Fantasy and the real world--now nightmares are starting to affect Mouse Island, the entire Kingdom is furious with Geronimo, and it is up to one mouse to set things straight and recover the ring.

On his way to the Grand Masked Ball and what promises to be a disaster of a date, Geronimo is once again whisked away to the Kingdom of Fantasy, and this time he must save the Princess of the Vanilla Fairies from an evil wizard who is using the pirate ship, Ship of Secrets, to gather magical objects to increase his power and take over the kingdom.