For the first time in paperback, we rejoin our heroine for her latest adventure just as she awakes to find herself in the body of a troll.

Her mum is worried sick, and now has to deal with the strange creature that seems to have taken Hilda's place.

Now, both of them are in a race to be reunited before Ahlberg and his safety patrol get the chance to use their new secret weapon to lay waste to trolls, and Hilda along with them.