The Thea Sisters embark on another adventure in Geronimo Stilton – Thea Stilton And The Ghost Of The Shipwreck. The story is narrated by Thea Stilton, Geronimoâs sister. In this book, the Thea Sisters go in search of a precious diamond called Jasmineâs Heart, which was lost in a shipwreck. The adventure starts during a marine biology session at Mouseford Academy, where they learn about the mysterious shipwreck and the diamond. They go on a mission to find the diamond, and investigate further when their teacher, Professor Van Kraken goes missing. The story continues with the Thea Sisters visiting China next, to recover another lost treasure. Books from the Geronimo Stilton Series are conceptualised and written by Elisabetta Dami, who uses the pseudonym Geronimo Stilton. Her experiences as a footloose traveler provide the inspiration and ideas that she needs to write her books. Apart from being a writer, Elisabetta is an adventure sports enthusiast, and also owns a publishing house – Edizioni Piemme. Other popular books from the Thea Stilton series include, Thea Stilton and The Mountain of Fire, Thea Stilton and The Ice Treasure, Thea Stilton and The Star Castaways, and Thea Stilton and The Secret City.