A once peaceful city has been turned into a complete nightmare by an extremely violent gang who call themselves "Hoppers". The officers of the Special Police are called in to mow down the Hoppers and save the city from certain doom! There are six rounds of pure mayhem as you mow down enemies in quick succession, as well as having to avoid innocent bystanders. Unlike many gun arcade games during this time period, Under Fire uses an infrared sensor to track gun movements instead of the timing of a CRT monitor, eliminating the need of screen flashes.