Wednesday Weeks just wants to finish Year Six without any more magical mishaps. But Gorgomoth the Unclean has other plans.

The tyrannical goblin king is back, and he's hot on the trail of the long-lost Stone of Power. If he finds it, it'll be goodbye school holidays and hello Third Age of Never-Ending Darkness.

To beat Gorgomoth to the stone, Wednesday and her friends must prove themselves worthy by passing three deadly trials. And so the race is on. But unfriendly cats, tomato sauce geysers and a pizza-train rollercoaster ride through a live volcano won't make their mission any easier. Will their magic and science be enough to stop Gorgomoth from taking over the universe?