For decades, the Wardens-a genocidal faction of near-immortal aliens called Echoes- have waged war against all who resist their rule on Earth. Dani survives by scavenging supplies while avoiding the local military and human-hunting Wardens. But when she discovers she's an Echo and not a human, her entire reality crumbles. When Dani risks her well-being to save a young boy from a violent kidnapping, the rescue makes her already tenuous existence...