FREYJA.Year 2030. The EXOFRAME, which can operate in any environment, showed its full potential under the sea. The underwater world became a new battlefield for the EXOFRAME. In the Barents Sea adjacent to the Norwegian Sea, Jan and Freya, workers for a private company in disguise, are in charge of maintaining the surveillance network systems to track submarines. Frequent incidents of undersea cables being cut is suggested to be sabotage by the Russians. Therefore, Jan and Freyas' underwater EXOFRAMES are also equipped with self-sustaining underwater robots equipped with explosives for self defense.