The tale of a young man's quest for revenge...
The game is pretty much a laid back adventure, in which you ask around the various areas you will visit, seeking information about your father's killer. Along with this however, is the use of young Ryu's knowledge of the martial arts. Ryu uses a style created by his family, and it is very powerful and known far and wide for its greatness. You may train Ryu with the various moves of his style, so he is better with them and will execute them faster and with better power. Ryu will also learn many new moves from people along his journey, and they will help you greatly in the fights you will encounter.
Along with real time fighting, there is also a system called ATB (Active Time Battle). In this mode, it is like a cinema, but while it is going you press the buttons that flash onto the screen, hit the correct button in time and Ryu will execute whatever needs to be done, but if you are too slow or hit the wrong button, then things will get bad for Ryu. This mode is used in some fights and also in things like chase sequences...miss too many times and Ryu will be defeated, or lose the person he is after, usually resulting in a Game Over.
In my opinion this is one of the best games ever made for the Dreamcast, and it is more than worth a play for those patient enough to play it...some find it boring, but the gripping story and fighting is worth the time.