Submersion of Japan

Dr. Tadokoro and Onodera pilot the Wadatsumi-1 toward the Ogasawara Islands to investigate unusual tremors. Their data reveals that the landmass of the Japanese archipelago is buckling and gradually sliding toward the Japan Trench. This discovery signals a looming disaster that could reshape Japan's future.

Onodera is introduced to Abe Reiko, and the two quickly become lovers. While relaxing on a beach, they witness a violent eruption of Mount Amagi that foreshadows the volcanic activity to come. The moment marks a personal turning point amid mounting scientific urgency.

A government meeting convenes with Prime Minister Yamamoto and key officials to assess the disaster. Tadokoro cautions that more eruptions and quakes are imminent, but his warnings are dismissed as alarmist. The decision-making stance highlights the tension between urgent science and political caution.

Watari agrees to fund Tadokoro's expeditions, enabling a national response framework. The funding comes as scientists prepare for a research submarine from France. During the negotiations, Mount Kirishima erupts, intensifying the sense of urgency.

Onodera resigns from his post as a submarine pilot to join Tadokoro full-time. He commits to the larger mission and dedicates himself to the plan for preventing catastrophe. The shift marks the beginning of a more unified research effort.

Further research confirms that the archipelago will be pulled into the ocean. The scientists project the collapse timeline and the scale of the coming disasters. The information reinforces the urgency of their two-phase plan.

Tokyo is struck by a massive earthquake, causing widespread devastation and claiming about 3,000,000 lives. The city’s infrastructure collapses under the seismic onslaught. The catastrophe abruptly shifts national priorities toward evacuation and rescue planning.

Three months pass as Tokyo struggles to recover, with Yamamoto mourning his wife and relying on Tadokoro's team and Watari's support. The group assesses that an even larger quake is imminent, setting the stage for a nationwide evacuation strategy. Public morale and political energy focus on action rather than denial.

Tadokoro unveils a two-phase plan: D1 to map seismic activity in the Japan Trench and D2 to evacuate the archipelago. Yamamoto begins diplomatic talks to secure refugee acceptance, while Watari outlines three options for D2. These proposals convert the crisis into a coordinated, international response.

Onodera, drunk and anguished over the public’s ignorance of the impending disaster, meets Reiko for the first time since Tokyo’s quake. The reunion lends a personal counterpoint to the unfolding catastrophe. It highlights how human relationships persist amid existential threats.

The Japan Meteorological Agency reveals the original two-year timeline has shrunk to ten months, forcing a new sense of urgency. Immigration talks accelerate and transportation capacities are increased amid a nationwide broadcast. The public is urged to prepare for imminent disruption.

A United Nations summit discusses possible relocation sites for Japan’s population. By this point, 2.8 million Japanese have already evacuated, while several coastal regions begin submerging. In total, about 63 million remain on the archipelago as the crisis intensifies.

Eleven days before the final sinking, Onodera remains in the field, hoping to reconnect with Reiko as rescue work continues. Yamamoto then declares a cessation of all JSDF rescue operations, signaling a grim pivot in the nation's response. The horizon of salvation seems to narrow with each passing day.

On his deathbed, Watari holds a final meeting with Tadokoro and Yamamoto. Tadokoro vows to remain in Japan and trusts Yamamoto to lead a future for the people. As a helicopter ferries Yamamoto to safety, virtually all of Japan has already sunk beneath the ocean.

Months after the catastrophe, Reiko rides a passenger train in Switzerland while Onodera travels in a crowded boxcar in the Southwestern United States. Both characters confront a world transformed by catastrophe and national tragedy, with love and stability in short supply.