From the inlay:
Are you: Dedicated to victory no matter the cost?
Are you: A terran patriot?
Do you have nerves of steel?
If you have then perhaps you can be a successful Drop Commando and help Earth in it's battle against the enemy Aliens.
In Sector 90 the player takes the role of a Drop Commando sent to open a chink in the defences of the Toor-Tamin, who have been at war with Earth for 200 years.
Drop Commandos are dropped in to enemy areas using powerful teleporters. These are powerful enough to punch through strong defences, but can only send one Commando at a time, are one way only, and cannot hit their destination with precision.
The Drop Commando must therefore search for the centre of the Sector 90 "Sector Intelligence Unit". To do so he must fight his way from where he is teleported in, and make his way through various locked doors where puzzles need to be solved.
At the centre, he must plant a bomb then escape within a 90 second time limit. If he succeeds, a gap will be opened in the Toor-Tamin defences, allowing the Terran fleet to break through.