Theatre Europe is a game for the Amstrad CPC, Atari 8-bit, Commodore 64, MSX and ZX Spectrum home computers. It casts the player as either NATO or the countries of the Warsaw Pact. The goal is to win the war against the other faction without destroying the world in nuclear war. The warpower of the Warsaw Pact side is overwhelming, so that winning with this side is quite easy. Playing the NATO side winning is only possible by halting the Warsaw Pact forces for a reasonable time. Entering the territory of the Warsaw Pact will cause the game to end with a global nuclear war and a score of 0%
Apart from the possibility of using nuclear weapons, the game also includes chemical and conventional weapons.
One unusual aspect of the game is that in order to initiate a nuclear attack, the player had to call a special United Kingdom telephone number to hear the launch code. (Versions of the game localized for the United States directed the player to a U.S. telephone number.) The telephone number connected the player to a recorded message, which started with the sound of air raid sirens and dramatically built up through various sounds of war to a huge explosion, followed by the sound of a crying baby. As this faded out, a voice stated, "If this is really what you want... the code is 'Midnight Sun'". (This was also printed somewhat obscurely in the manual.)
The title music includes the main theme from John Lennon's 1969 song, "Give Peace a Chance." According to PSS, the game is based on extensive research into Warsaw Pact and NATO military strength. Developer Alan Steele stated that he was alarmed to find during testing, when the computer played itself, that the Warsaw Pact always won a conventional war overwhelmingly, forcing NATO to either surrender or begin a nuclear war. PSS adjusted the game to give NATO a chance to win.
Zzap!64 stated "This triumph of gaming and common sense should prove the most popular war game yet ... the program presents a realistic simulation that actively discourages nuclear war". Computer Gaming World criticized the action sequences as too simple, stating that "their entertainment value drops faster than a banana republic's currency". The magazine found the strategic game better but too simplistic, and the computer opponent was too weak but the game lacked a two-player mode. The game was voted strategy game of the year at the 1986 Golden Joystick Awards.