Twelve-year-old Petrel is an outcast, living on an ancient icebreaker that has been following the same ocean course for three hundred years. The ship's crew has forgotten its original purpose and has broken into three warring tribes. Everyone has a tribe except Petrel, whose parents were thrown overboard for alleged crimes. She has survived by living in the dark corners of the ship, and speaking to no one except two large rats, Mister Smoke and Mrs...