In a dystopian sudden, a girl wakes up in a dimly lit, claustrophobic room with no memory of who she is. She discovers a cold metal collar around her neck and a mysterious number, 100003, burned into her arm. A voice crackles through an unseen intercom, revealing that she has been chosen for a brutal and mysterious experiment along with others. The man behind the voice, who refers to himself as their overseer, announces that they are now participants in a deadly game with no rules. The overseer watches with a twisted grin as they must band together—or betray each other—to escape this nightmare alive.