Cinder, the cyborg mechanic, returns in the second thrilling installment of the best-selling Lunar Chronicles. She's trying to break out of prison - even though if she succeeds, she'll be the Commonwealth's most wanted fugitive. Halfway around the world, Scarlet Benoit's grandmother is missing. It turns out there are many things Scarlet doesn't know about her grandmother or the grave danger she has lived in her whole life.