The smugglers arrive on the island demanding the emerald, unleashing a violent confrontation. America reveals that she hid the stone, but when she tries to recover it, she discovers it has disappeared. Nazareth guides Charles Mendoza and his group through the tunnels, but something lurks in the dark: a terrifying creature attacks them mercilessly. The battle for control of the island has begun.

Immediately after the explosion that killed Noah, a new bomb shakes the group to its core. With casualties, injuries and no shelter, survival hangs by a thread. While some try to keep the camp going, others venture deep into the island... where something has been waiting decades to be discovered.

With supplies exhausted and Máximo on the brink of death, the group risks everything trying to open the armoured door of the Soviet base. But what they find on the other side is not just supplies: there is life on that island no one expected, and not all of it is welcome.