When Geronimo finds he will be spending the holidays alone he becomes depressed, but then discovers an amazing surprise that teaches him the true meaning of Christmas.

As the tenth anniversary of Geronimo Stilton's first book approaches, his laptop with the manuscript for his latest book is stolen and he and his friends must track it down in time to share the new book at his anniversary party.

Geronimo Stilton is summoned back to the Kingdom of Fantasy, but he finds Blossom, Queen of the Fairies, surrounded by dark fairies and behaving very coldly--and it is up to Geronimo to figure out just what is going on and find the allies he needs to freeBlossom from the evil spell that is affecting her.

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.

Geronimo is taking his Benjamin on a trip to Rome to learn the city's history (and keep him from failing fifth grade), but when they arrive they are immediately pulled into the investigation of the "ghost" of a gladiator that seems to be haunting the Colosseum and scaring tourists away.