Time travel. It's dangerous, traumatic, a high-risk pursuit. It's also the most thrilling thing you'll ever do. Sam Winterson has gone missing in time. One of his heists has gone seriously wrong, and if he doesn't surface soon, his enemies will take their revenge on his mother. As the time traveler who rescues lost time travellers, Elidi Ives is the only one who can help. But there are three problems: Nobody in her daily life - including her boyfriend Delaney - knows that time travel is possible, except... ... her twin sister, Luna, who refuses to take on this mission for her, because.. Sam is El's ex for a reason. But does that mean she should leave him to die?