The islands of Prospera lie in a vast ocean: in splendid isolation from the rest of humanity, or whatever remains of it. . .

Citizens of the main island enjoy privileged lives, attended to by the support staff who live on a cramped neighbouring island, where whispers begin to grow into cries for revolution. Meanwhile, life for Prosperans is perfection - and when it's not, their bodies are sent to the mysterious third island: a facility named The Nursery, to be rebooted and restart life afresh. Proctor Bennett is a Ferryman, who shepherds the soon-to-be retired into the unknown.

He never questioned his work until the day he is delivered a cryptic message:"The world is not the world..." These simple words unravel something that he has secretly suspected. They seep into strange dreams - of the stars and the sea - and the unshakeable feeling that someone is trying to tell him something important. Something greater than anyone could possibly imagine, which could change the fate of humanity itself...

'A mind-bending novel full of big ideas and a rollercoaster's worth of twists and turns - so powerful and thrilling!' ANDY WEIR, author of The Martian