The year is 3326. Nigel Sheldon, one of the founders of the Commonwealth, receives a visit from the Raiel—self-appointed guardians of the Void, the enigmatic construct at the core of the galaxy that threatens the existence of all that lives. The Raiel convince Nigel to participate in a desperate scheme to infiltrate the Void. Once inside, Nigel discovers that humans are not the only life-forms to have been sucked into the Void. The humans trapped there are afflicted by an alien species of biological mimics—the Fallers—that are intelligent but merciless killers. Yet these same aliens may hold the key to destroying the threat of the Void forever—if Nigel can uncover their secrets.