Aquanox 2: Revelation

It is the 27th century, and humanity has fled the surface of the Earth, plagued by radioactivity, into the depths of the ocean. William Drake is the last offspring of an old aristocratic family. After the death of his grandmother, the young man sails off on a freighter belonging to Drake Enterprises. Soon, a group of mercenaries attack his vessel and take control of it. The attackers spare William's life, but he has no other choice but to link his fate to theirs from that moment on.