It's 1999,and the U.S. Government is no longer refusing to acknowledge the existence of UFOs. As a matter of fact, there are so many of the damn things buzzing the earth that an interplantary task force called the Extraterrestial Combat Unit, or XCom, has been formed to track down the alien visitors, and you're in charge.

	 In the world of UFO Enemy Unknown, a PC strategy game from MicroProse, these tourists from another galaxy aren't ET clones searching for pay phone to call home. These aliens are out to rape our women, enslave our children, and generally turn the world into an extremely miserable place to live. As the UFO onslaught grows, you must try to build XCom into a force capable of turning back the aliens.

	 This is not a game to play if you're in a hurry. As a matter of fact, this is not a game to play if you're the type of person who needs a definitive goal to try and reach. This is so vague, I couldn't find any specific reference in the player's handbook as to what it takes to win, although logic dictates that chasing the aliens away from Earth would probably fit the bill. The designers give you a very basic foundation of information to start. Then, it's up to you to spend enough time with the game to learn what it takes to succeed.

	The best place to start UFO Enemy Unknown is with the three-part gameplay tutorial. This will show you how to move around in the Geoscape, which is where you locate your XCom bases and track UFOs; how to move your troops around in the battlescape when you actually engage the aliens; and how to establish and equip your bases.

	  Since this game quickly reaches the point that you can't swing a dead cat around without hitting a UFO, tracking the aliens is simple. After our radar screen alerts you to their presence, you attempt to chase them down. This isn't always automatic, since the alien vessels are quicker than yours. If you can catch one, be careful to shoot it down over land, since you can't track aliens on the ocean floor. Then, return to base and send out another plane to the crash site with a team of soldiers that you hope can vanquish the galactic villains.

	  Once you reach the UFO crash site you're working in the battlescape. After the aliens completely embarrass you in y our first four or five meetings with them, you eventually figure out that tactics are extremely important, and that - once again - patience is a virtue.

	You can bring as many soldiers as the plane will hold to fight the aliens. A helpful hint _ try to keep at least one crew member in the plane after you land. If things go poorly, you'll need to have at least one survivor in order to fly back to your home base and explain what went wrong.

	When you're in the battlescape fighting the aliens, this is a turn-based game. Each of your soldiers has a set number of time units, and every action they take requires a certain number of those units. Once you've finished moving your forces, you end your turn and the alien forces respond.

	At the beginning, you're working with a group of rookies who can't shoot straight; are susceptible to panicking, which means they can't move for one turn; or even worse, go berserk, which means you have to kill them before they wipe out your landing party. However, if you exercise patience _ have I mentioned that phrase lately? _ your soldiers gain experience and become more effective as the game wears on.

	While your rookie soldiers are out in the field serving as alien bait, your scientists and engineers are back home trying to hurry along human technology. A successful mission helps this process along, since your research teams can improve their own work by examining alien artifacts. After the research process ends the engineers take over and manufacture the new invention. This means the managing your budget is one of the keys to doing well.

	As the alien presence grows, you come face-to-face with political reality - you can't completely trust the governments that are providing XCom's funding, since they may be in cahoots with the aliens. Also, even at the dawn of the 21st Century, politicians are still front-runners. If one of your missions fails, there's a virtual stampede of governments all announcing cut-backs in their financial aid to your brave, albeit clumsy,  group of UFO fighters.

	It's been awhile since I mentioned the P word, so I'll say it again _ you had better be patient if you start this game. I spent parts of three days playing this beast on the beginner's level, and got nowhere near the point of being successful, much less finding out what it takes to beat the aliens.

	What I'm trying to say here is that UFO Enemy Unknown is an easy game to learn, but an extremely difficult one to master. Each time you play you advance a little further before the aliens completely destroy yet another mission, sending you back to your home base cursing the existence of the universe. This is a test that you should be prepared to fail on a consistent basis. However, if you ever reach the point where you actually prevail against the evil invaders, no doubt your joy will be boundless.