All Cole has left in the world is her boy, Miles.

With men now a prized commodity, keeping him safe means breaking hastily written new rules - and leaving her own sister for dead.

All Miles has left in the world is his mother.

But is one person enough to save him from the many who would kill to get their hands on a living boy?

Together, Cole and Miles embark on a journey across a changed, hostile country, towards a freedom they may never reach. And when Cole's sister tracks them down, they'll need to decide who to trust - and what loyalty really means in this unimaginable new world.