During a hot-air balloon flight, the Thea Sisters discover that the turtles have vanished from Turtle Island! If that wasn't alarming eugh, dangerous drums of a strange oil are spotted off the shore of the island-a disaster waiting to happen! The Thea Sisters are surprised that ne other than Vissa De Vissen wants to help them save the island and the turtles! All seems lost until Nicky and Paulina spot a couple of turtles entering a mysterious underground cave! There are mysteries within mysteries, but the Thea Sisters are determined to solve them all and save the day.
THEA STILTON was born in New Mouse City, Mouse Island. She is a special correspondent for The Rodent's Gazette, Mouse Island's most famouse newspaper, which is edited by her famouse brother, Geronimo Stilton. A graduate of the prestigious Mouseford Academy, Ms. Stilton is a visiting professor of journalism at Mouseford today. She is also the author of numerous mystery novels based on the exciting lives of her friends and former students, the Thea Sisters. In her spare time, Ms. Stilton loves to travel and go on fabumouse adventures.