On the Beach

The USS Charleston (SSN-704) is deployed on station in the wake of a devastating nuclear exchange. Dwight Towers commands the submarine as the standoff between the U.S. and China escalates into global devastation. The crew processes that most of the world has been destroyed and their own lives are at risk.

The Charleston seeks refuge in Melbourne, Australia, where fallout has not yet reached. Communications indicate radiation will arrive within months, heightening the crew's sense of doom. Towers cedes operational control to the Royal Australian Navy and is summoned to a briefing about an automated broadcast from Alaska.

The submarine is sent to investigate the automated digital broadcast originating from Alaska. Towers is joined by Australian scientist Julian Osborne and liaison officer Peter Holmes on the mission.

Towers and his executive officer go ashore and find no survivors; they enter a house and see a dead family, triggering reflections on their own loved ones. The grim encounter underscores the scale of the catastrophe.

The crew traces the broadcast to a solar-powered laptop broadcasting a documentary via satellite. The discovery reveals that the warning and information are coming from a fragile, isolated device rather than any military signal.

During the Alaska mission, Towers' executive officer punctures his suit and injures his leg but conceals the injury from Towers. The injury foreshadows his impending decline from radiation exposure.

Rather than returning to Melbourne, Towers orders a route to San Francisco, the crew's home city. The Golden Gate Bridge lies collapsed and the waterfront is ruined, illustrating the extent of decay.

A crew member from San Francisco abandons ship to die in his hometown, but his shipmates leave him behind, citing that his radiation sickness makes survival impossible.

On their return to Melbourne, the executive officer collapses from terminal radiation sickness. Towers tends to his friend and, at his request, euthanizes him to end his suffering.

As the anticipated cloud approaches, Melbourne's social fabric unravels into anarchy and chaos. The society struggles to cope with imminent doom and dwindling resources.

Radiation sickness intensifies; the public lines up for government-issued suicide medication. Peter, his wife Mary, and their daughter Jenny fall ill, and Peter administers the dose to their daughter before taking the medication himself.

The crew, now gravely ill, asks to take the Charleston on a final voyage to San Francisco to die together. Towers agrees, seemingly abandoning Moira, who is about to take her own pill and watches the ship depart. Towers joins her at the end, implying they will share the end together.