It is the year 2101, and human beings on Earth have colonised the far reaches of the solar system. Fossil fuel resources on Earth have long since dried up, so the planet Pluto is constantly mined for nuclear fuels to provide energy for the ever-growing human population. Dozens of attacks have been reported on one of the nuclear fuel processing plants. The facility has been bombarded with shells by unusual creatures flying through space at enormous speed. Conventional ground weapons are ineffectual. It is up to one person to fly out into space, and defeat the aliens in a specially modified space craft. You are that person. After a lifetime of bounty-hunting and mercenary work, you realise that now is your chance to go straight, clear your name and become a hero - defeat those aliens, collect the coins, and save Pluto!