You command an American Los Angeles or Soviet Alfa class submarine. You prowl throug a dark, undersea world, carrying out dangerous missions that require predatory cunning and bold action. In peacetime, you track and hunt potential enemies. In war, you ambush enemy convoys and defend your warships; stalk ballistic missile submarines and duel other hunter/killers strike at inland targets from enemy waters and live to tell about it. All the major systems of a modern attack submarine - sonar, weapons, navigation, helm, radio and periscope - are at your disposal. Over 40 separate controls let you feel what it's like to operate the world's most sophisticated - and deadly - defence technology. At the same time, crew transmissions and pictures remind you that as captain you manage men as well as machines.