Two elite soldiers, Bill Rizer and Lance Bean, are dispatched to stop an extraterrestrial threat bent on global conquest. Depending on the version, the action unfolds either in a distant future on a remote archipelago or in contemporary times on an uncharted island, where players must confront the mysterious force known as Red Falcon before it can establish dominion over Earth. Armed with heavy weaponry and combat training, the commandos fight through hostile terrain and overwhelming opposition in a race against time to prevent catastrophe.