Following on from The Howling-Tower, this is the second story in this fantastic trilogy that really breaks boundaries with its original content and strong voice. After escaping the Howling-Tower with Mops, Benjamin is determined to find out where his parents are, after hearing stories about them. But the two friends are unable to avoid capture again, and after witnessing the cruelty of the gallow-boat, where he finds his father as one of the saps used to power it, they are taken to be pet-saps by King Antonius and Queen Dearie. When Benjamin rebels violently against the Queen's cruel attempts at obedience training, Benjamin finds himself facing a worse horror than he ever could have imagined! What will be the future for him and Mops?