Fire Shark takes place around a small island in the South Pacific, where you must navigate through increasingly difficult levels while avoiding aerial, aquatic, and ground enemies that fire missiles at you. Your plane has been modified to shoot lasers and drop powerful bombs, giving you a unique challenge.
The gameplay involves continuously scrolling through levels, each with its own set of challenges and power-ups. You can land on a runway between levels to refuel and maintain your plane, earning bonus points for collecting certain icons. Power-ups can be obtained by destroying enemies or buildings, granting you weapon upgrades or additional points.
As you progress through the game, you'll unlock new weapons, including the Wide Shot and the Super Fire. The Wide Shot is a weak but versatile weapon that requires multiple hits to take down enemies, while the Super Fire fires continuously when held, making it your strongest option.