'A strange dog appears in Nim's living room, and Mum orders him to get rid of it.But when Nim grasps its collar, he and the dog are swept away by a mighty wind. It takes practice to control a wind-riding chain and Nim has some scary adventures trying to take the dog back to its home. He will have to be brave and clever if he is to defeat the cat-girls and save his world.'
Source: Back-cover blurb.