The Thea Sisters are five fun lively students at Mouseford Academy on Whale Island who want to be real live journalists just like their hero Thea Stilton. Between classes friendships crushes and some bizarre mysteries to solve they find life to be a never-ending adventure! Colette Violet Pamela Nicky and Paulina are working on a historical restoration when they learn about an ancient Viking vessel that sank off the shore of Whale Island. Rumor has it that the ship is full of treasure and whats worse some shadowy figure is plotting to steal it! If Mousefords best investigative journalists cant crack this case Whale Island will lose one of its most important cultural artifacts before its even found.