They are coming to get you. Hide. Hide. Hide. The children of Perses have been receiving this message on repeat from Earth for weeks. Christopher, Elena, and the other survivors of the attack on their space colony know two things: Their victory over the Landers will be short-lived and a new wave of attacks is imminent. New Landers arrive sooner than expected. Led by the ruthless Kirk Thatcher, and armed with a new lethal kind of digger, they vow to hunt down and destroy everyone. The kids have nowhere to go but underground. Again. But resources and patience are running low, and the struggle to keep everyone safe is complicated by all the infighting. As Christopher bears the burden of leadership, he also has to decide whom he can trust. There are no easy answers. And with deadly consequences on the line, there is no room for mistakes.