Based on the air-sea battle Arcade game, Polaris puts you in command of a Polaris class nuclear submarine. One day, while you are patrolling deep in hostile territory, war is declared. Suddenly, you are bombarded with bomber squadrons, enemy submarines, enemy destroyers and dive-bombers. Your job is to take down as many enemies as you can before retiring to a watery grave.
Polaris is divided into three stages. In the first stage, hostile submarines prowl beneath the surface of the sea while high-altitude bombers drop depth charges from above. You can launch missiles at the planes and fire torpedoes at the subs. If you are lucky or use the proper strategy, you can fool the planes into destroying the submarines.
The second stage is similar in design and gameplay, but the planes execute dive-bombing loop-de-loop runs, getting dangerously close to the surface of the water.
In the third stage, the playfield shifts to an overhead perspective. Here you must navigate the Polaris through labyrinthine channels while shooting or avoiding channel mines.