Overview

• The episode explains the catastrophic eruption of a supervolcano in Antarctica, triggering massive tsunamis and widespread devastation.
• The disaster led to a nuclear arms race, further escalating global destruction and resource competition.
• President Cal Bradford chose to deploy a massive EMP over launching nuclear weapons to preserve humanity's chance of survival.
• Flashbacks reveal Xavier Collins' family separation during the evacuation and hints of his wife’s survival on the surface.
• The finale is set to resolve lingering mysteries, including the identity of the president's assassin and the fate of key characters.