The Thea sisters continue the search for the seven ancient treasures, using the clues found in Aurora Beatrix Lane's travel diary to find a fabulous emerald which once belonged to Cleopatra--a quest that leads them from Moscow, to the Sahara, and finally Bolivia.

When Geronimo Stilton learns someone wants to steal the antique silver skates being offered as a prize in Mouse Island's annual winter Ice Skating Championships, he races to uncover the mysterious thief and save the prize.

Using the clues found in Aurora Beatrix Lane's travel diary, the Thea Sisters continue their search for the seven lost treasures; and the object this time is the Ring of Eternal Love, a journey that begins in Verona, Italy, with the story of Romeo and Juliet and takes them around the world.

When a haunted dinosaur wreaks havoc across Mysterious Valley, Creepella tries to tackle the beast and brings Geronimo along for help.

Just as Creepella is about to interview Hector Spector, the owner of the Galloping Ghost Circus, strange things start happening around Cacklefur Castle, and she investigates.

"When two new students - Bradley and Irving - arrive at Mouseford Academy, they become friends with the Thea Sisters instantly. The crew begins to plan Whale Island's first ever theater festival and costume ball! But Bradley is keeping a secret from his new friends. What will happen when they find out who he really is?" -- Back cover.

"Now that the terrible Toney Sludge has escaped from prison, it's up to Geronimo Superstilton and the Heromice to defend Muskrat City from the notorious Sewer Rats and stop an enormouse blackout! Will our heroes be able to defeat their enemies without losing their fur?"--Page 4 of cover.

"The jewelers of Muskrat City are in trouble. A thief has been stealing precious diamonds, and the thief is ... invisible! Can the Heromice protect Duchess Marilyn Mousekovia and her precious Star-Studded Gemstone during her visit to Muskrat City? And more important, will they catch the elusive Invisible Thief?"--Page 4 of cover.

Geronimo, Thea, and Trap are exploring a mysterious old castle built by the founder of New Mouse City. Can they unlock all its rooms and discover its secrets?