Since her mother's death, fifteen-year-old Jem has kept a secret. When her eyes meet someone else's, a number pops into her head - the date on which they will die. Knowing that nothing lasts forever, Jem avoids relationships, but when she meets a boy called Spider, and they plan a day out together, her life takes a new twist and turn. Waiting for the London Eye, she sees everyone in the queue has the same number - something terrible is going to happen.