As a Luna City police officer assigned to Sector Nine, the home of the "toughest thugs in the galaxy", the player controls a lunar rover that travels to the right over the horizontally scrolling surface of the Moon. Craters, mines, and other obstacles on the ground must be shot or jumped over. Three types of flying UFOs attack from above and must be shot down. One of the flying enemies has a weapon which creates a crater when it hits the ground.
Gameplay takes place on two courses, each divided into 26 checkpoints identified with letters of the English alphabet. Of these, the five major checkpoints—E, J, O, T and, Z—denote a new "stage" with a new background and theme; for example, the third stage starts at J and introduces mines. The top portion of the screen shows a timeline-style map of the course, with the major checkpoints marked. Above the map is an indicator of the current checkpoint, the time spent in the stage, and three indicator lights: the top light indicates upcoming enemy aerial attacks, the middle one indicates an upcoming minefield, and the bottom one indicates enemies approaching from behind.