In 1973, an alien species known as the BETA invaded Earth. In response to their seemingly endless numbers and resistance to conventional tactics, humanity developed manned bipedal machines known as Tactical Surface Fighters — a weapon system designed for the sole purpose of countering the alien threat. But TSFs alone weren't enough, and humanity has been trapped in a neverending war for decades, slowly but surely being driven to the brink of extinction.

February, 2004: Professor Kouzuki's last-ditch gambit has failed, and Alternative IV is no more. The fate of mankind now rests on the success of Operation Babylon — a massive, simultaneous detonation of the mysterious “G-Bombs” over every single BETA hive on Earth.

But in the blink of an eye, what seemed to be the hour of final victory for humanity in the decades-long BETA war turned into a colossal defeat. The alien invaders were seemingly destroyed, but at what cost? Europe and Asia were lost beneath the waves, and much of the remaining land masses are now barren deserts of salts, unfit for human life.

The apocalypse has come and gone, but mankind remains. This is the story of the few who were left behind to survive on a dying planet. This is the day after.

Stranded in the middle of the South Pacific, the future looks bleak for the men and women of the TSF Carrier USS John F. Kennedy. With their food supply dwindling, their communications down, and no improvement in sight, tensions are steadily rising among the crew, and many are fast approaching their breaking point.

Lieutenant Will Collins has been entrusted with the thankless task of conducting recon in the nearby salt flats. After weeks of uneventful flights, his luck changes one fateful day, when he comes across a survivor: Lieutenant Lilia Kjellberg. And while this seems to have been a fortunate happenstance at first, Will soon finds himself at odds with the new addition to the crew, as their beliefs clash on a fundamental level.

Can these fellow surface pilots set their differences aside and work together to survive, or will their rivalry only hasten the JFK's downfall?