The player is an Allied soldier whose orders are to infiltrate the top-secret fortress called the Eagle's Nest (which consists of four castles), rescue three allied saboteurs being held there, save art treasures the enemies have stolen, and then destroy the Nest with explosives.

The player depresses the firing button to fire the machine gun, which carries enough ammunition for 99 shots. Enemies require two well-placed shots to eliminate, and the ones sitting at a table only require one well-placed shot.

The player can sustain up to 50 shots from enemy soldiers. While inside the castles, the player finds crates which may contain art objects or explosives. The player can also find ammunition dumps, first-aid kits, and goods in the castles.