Washington and Moscow are the capitals of the Superpowers, but the Cold War is fought at the front: in Eastern Bloc countries like Frobnia and adjacent neutral countries like Litzenburg. In these countries, where all strangers are suspect and all actions observed, paranoia and vulnerability are inescapable. In these countries, innocent travelers get caught in the web of international espionage. This is the setting for Border Zone.
Border Zone consists of three chapters. In each chapter, you play a different character (an American businessman, a Western spy, and an Eastern spy) involved in the assassination attempt of an American ambassador. Each chapter is a story unto itself, with its own unique puzzles and goals. The chapters take place at different times and at different locations; as a player, you will get the most satisfaction if you play the chapters in order.
Border Zone has a built-in clock which drives the story forward. Unlike other Infocom stories, the clock in Border Zone continues to tick even while you stop to think. So if you find yourself in a dangerous situation, you can't just sit back and relax. Whether you type in a command or not, characters will move around, events will happen, and the story will proceed.