The family attends Mallory’s fencing contest at school. During the contest, Jared finds a boy identical to him going through Mallory’s bag. He transforms into a smaller kid when Jared attempts to scare him with his knife. When Jared and Simon discover that Mallory has disappeared, they search for her in an abandoned quarry, but wind up being kept prisoner by dwarves. Mallory is revealed to be sleeping in a glass-coffin dressed in medieval garb (similarly to Snow White), with the dwarves saying she is now immortal, so long as she stays in the coffin. Escaping their cage, the twins free Mallory and meet a strange creature, called a Knocker, who tells them the way out by listening to the stones. They next see a huge metal tree, made by the dwarves, the Ironwood Tree. After a narrow escape from the dwarves’ mechanical dogs, they make their way out of the tunnel but have to hide before leaving. On the side of the socks is the tree, and the cable in the front is the journey to find each other.