"You are the Beamrider. You must clear the Restrictor Shield that surrounds the Earth. Enemy Sentinels guard each sector, so beware..." So says the instruction sheet but the game itself is one of those zap-'em-all shooting games with a 3D effect (Well, it's supposed to be). It's a sort of Juno Fast-gone-Tron game as you see yourself riding on a grid with the enemy saucers approaching and shooting back at you.
The thing about this game is that, although there are many kinds of enemy and features, graphically it is very dull. And no wonder - Beamrider was first written for the Atari VCS and ColecoVision games machines, which went out of fashion ages ago. Activision had plenty of time to improve but the graphics are just the old versions - poor.
This kind of zapping game is now out of fashion in this country, and I don't know why Activision bothered.