After a chance meeting with a group of Faeries, Hilda has changed. Now Hilda, Frida and David have to track them down to change her back, but someone else has their eyes on the Faeries too, it seems.

It's easy to say that Hilda is able to get through any adventure. She wrestled ghosts, rescued a baby weather spirit, and even stopped war between her family and the elves. What happens when something unexpected happens, and her Mum is already at work? Can her friends help her with her new problem?