The story behind 1985 goes along the lines that Big Brother, he of 1984 fame, has been destroyed, and humankind has to sort themselves out. Key to your ongoing existence is energy, in the form of nuclear plasma. Guess what? Somebody's nicked it all and hidden it away on four alien planets.
Your only means of locating your energy is by means of a flakey old lunar lander-style craft, which can only rotate, thrust and activate a tractor beam. You must pilot this craft to the neighbouring planets and fetch back your precious plasma, negotiating caverns and aliens along the way.
If you haven't guessed already, 1985 is something of a Thrust derivative, though this game has a difficullty level that makes it almost impossible.
Sadly this cliff-like learning curve gets in the way of what is otherwise a pretty good game.