Two-thirds of our planet is covered by water. The vast blue water is largely unexplored - making it the ideal place to hide. An unknown alien menace has been lurking deep below the surface waiting for the opportunity to attack. The time is now. This aquatic alien Force has launched an extreme attack against mankind, and it's up to you to fight back and preserve civilization before it's too late. Channel the elite soldier inside of you and battle against a deadly enemy from another world.