In the evening sky on a very clear night you may just see a small and unassuming planet glowing in the far recesses of the deepest galaxy.
So advanced is this planet that its defence system is completely controlled by a powerful computer. Things have run smoothly for aeons, but lately the computer software has started to throw up a few bugs - most seriously, it's losing its ability to distinguish between enemy and friendly craft.
The malfunction is causing havoc on this peace-loving planet. Now someone (OK. YOU) must destroy this computer before it's too late. Your mission codename is Z.
The computer lies within the fourth dimension - a place only talked about, because no-one has ever got there. To reach this strange world you must travel through a hostile wraparound scrolling play area.
You take with you three ships; their energy supplies are damaged by contact with enemy craft, but slowly, constantly, automatically replenished.
Within each zone is a central transporter unit which will take you to the next level. But first you have to capture an energy capsule, which can be used as a bomb to break open the transporter.
Each level is protected by different forces. On Level One, a squadron of 20 fighters assisted by natural meteorites attempts to stop you. The countryside battle zone of Level Two presents a deadly collection of evasive Flying Saucims (sic) emitting directional missiles. And on the lunar landscape of Level Three you're confronted by great big Mother Ships throwing out a collection of homing missiles.
On completing the third level you gain an extra ship to help in your final battle in the Nightflight zone, where you need five direct hits to finish off the enemy.
'Z is yet another over-simple monochromatic scrolling game. The sound is mumbly and unimaginative and there's no addictivity. Steer well clear of this one.'
'Monochrome shoot-'em-ups seem to be quite popular now, so ten out of ten to Rino for style - but minus several million for good thinking. Z is unattractive and unaddictive, and I wouldn't buy it.'
'Z is pathetically simple. All it boils down to is a graphically neat, sonically awful scrolling shoot-'em-up, of which there are many. Still, it's quite playable for a while...'