Daimaju Gekito Hagane no Oni

Synopsis:

In 1999, a revolutionary science experiment was held at the island-located San Sarah research center. An unknown energy particle was discovered, and subsequently named "Quark of Malhuder." With this new particle at their disposal, a satellite-equipped laser weapon was constructed; but during its test run, a strange vortex opened in the skies and a large mass descended into the ocean. Three years later, one of the experiment's unwilling participants, Takuya, receives a letter from another participant (and friend), Haruka. In the letter, Haruka begs Takuya to return to the island and put an end to his misery - a call that Takuya immediately sets forth to investigate. The person Takuya finds at San Sarah is not the friend that he remembers; and soon, something even more dangerous will awaken...