The game puts the player in the future as a pilot of the Tigershark. Japan has been flooded due to unsafe methods of producing energy via underwater stations, causing extreme earthquakes all over the country. It lies in the Russians interests to steal all this technology, and it's up to the player to prevent that from happening.
Each mission (of which there are 10 in total) begins with a short breifing from an unkown female voice. The missions are usually "Destroy this target(s)" or "Rendevouz". The game can utilize a joystick for control, as well as a normal keyboard with arrowkeys by default. Gameplay takes place underwater for the most part, but it is also possible to steer on top of the surface as well.
A less known "secret" of Tigershark is that the retail disc contains several random pictures (not used in the game). One of the pictures is of an underwater creature however not an actual tigershark. The other pictures looks rather like private vacation pictures.