A cross between a simulator and an out-and-out shoot-'em-up, providing entertainment in direct relationship to the skill you are able to bring to the game. No way can you simply load up and start blasting; there's some homework to do first.

I had to read the submarine's manual several times and plod through a few humiliating rounds before getting my act together. To the best of my knowledge all the essential instrumentation is displayed flanking a central monitor that flips between map, sonar and periscope mode at the touch of a key.

First you must locate a convoy on the map, set your course via the compass and increase speed: slip under the surface and out of view when you hear the warning bell and switch to sonar. Refer to the hydrophone chart (the peaks are the enemy), now up with the periscope and scan the horizon. Note the scrolling screen as the enemy looms into view, steady her up and release a torpedo.

After all the swotting, success is sweet but there is no time to rest on your laurels. You will want to bag a few more targets and may have to *crash dive*... run silent - run deep. On to pastures new, but first check the batteries, the fuel and air supply plus any damage sustained. While on predatory missions near the coast or any of the Mediterranean Islands watch out for the rocks beneath your keel. Quite a lot to monitor and therefore plenty of scope to improve your playability ability... months of fun in fact.

I was really impressed by the good use of graphics married to relevant, varied sound effects.