There is a crisis in the Starlight Kingdom, one of the fantasy worlds: its stars, powered by a special kind of stardust, are fading and may soon go out forever, leaving the Kingdom in darkness--so the Thea sisters and Will Mystery set out for Brightstar Castle to discover what is wrong, but first they must overcome the obstacles and challenges that the fairies are placing in their way.

While the Thea sisters are at the excavation site of a dig at Hierapolis, Professor Brenninger unearths a series of priceless and very old figurines, but the Thea Sisters think the discovery may be a scam and investigate.

Thea Stilton and her sisters journey to the land of Minwa, a realm linked to the legends of Japan and wrapped in mysteries and enchantments, to discover why the realm's special lotus flowers are disappearing--and why their diappearance seems to be threatening the whole land.

When one of the Thea Sisters' favorite mystery writers goes missing, the five mice travel to the author's native Iceland, where they reconstruct the dangerous plot of his latest novel in the icy terrain to piece together clues.