The galaxy is trapped in an endless cycle of extinction. Every 50,000 years an ancient machine race invades and with ruthless efficiency wipes out all advanced organic civilization. They leave behind only the scattered ruins of technology, destroying all evidence of their own existence.
Well the game is an undeniable classic, but it didn't aged too well in some regards. Driving is tiresome and equipment system is way too clunky and unintuitive.
Story starts off as seemingly cliche and pompous dialogues don't help, but the further it goes on the better it gets.
Side missions aren't that good, however, because there's only 4 types of "dungeon" layouts repeated over and over again, and 50% of all locations is one layout. Exteriors of planets are troublesome because of terrible handling on Mako.
And there's way too many side missions in which you have to simply look for objects like minerals or artifacts throughout the entire galaxy.
But combat is fun, companions and other characters are well rounded and the story, again, gets really interesting further on. And even some of the borderline boring and repetitive sidemissions have some interesting details about them (Rogue AI mission ending, for instance) It's just a bit of a shame that morality in the game is completely binary.