An explosive new novel by the author of the National Book Award-winning Challenger Deep and the New York Times bestselling Arc of a Scythe series, about the limited ways we see our world--and how a jolt out of the ordinary can upend the universe.

All it takes is one hit on the football field, and suddenly Ash's life doesn't look quite the way he remembers it.

Impossible though it seems, he's been hit into another dimension--and keeps on falling into universes that are almost-but-not-really his own, each one stranger than the last.

And if he isn't careful, the world he's learning to see more clearly could blink out of existence...