You are at the controls of a space cruiser and your mission is to track down and destroy Klingons with phasers and photon torpedoes. You have a protective shield which can deflect some Klingon fire. There's a battle computer to work out the energy you need to make jumps into hyperspace if the Klingons prove to be a little too troublesome. And there's a once-only panic button if you are about to be destroyed.