I remember playing this game back on the PS1. The main character is a badass who works as a Merc for the Rebellion. Due to this flexibility, he isn't a main part of the alliance, but he certainly prefers it than working for the empire.

The story to this game is you play as this character during the events of Star Wars Episode IV, and V I believe, it has been a while since I completed this game. The first mission involves you doing something none of the other Rebel Infiltrator's had done, retrieve the blueprints to the death star. As any Star Wars fan knows, the plans are what revealed a weak point in the Death Star's defences and the leader even mentioned how they lost many men attempting to get that information.

You are then called in because a Rebel base when silent from an attack, but this was no ordinary attack as the entire base was taken out and if it was a army, they would've seen it coming and evacuated or at least shot many of them down before going into hiding. It's then revealed that one of the most interesting enemies of the Star Wars franchise is created here. The Dark Troopers. Commando Troopers that are far more powerful and destructive than you're average trooper as they can take out entire bases by themselves.

Many weapons you get are references to the ones from the film such as blaster pistol, blaster rifle, Thermal Detonator and quite a few interesting and creative weapon designs.

It's well worth a play if you can get a hang of the controls and remember how Lucas Arts used to make years ago as this was during the age they made adventure games and before they went lax and started making half-assed games.