The world Ray WInninger creates in this is an amazing dystopian future where technolust has taken over even our basest motivations and war is the currency. . . So he pretty much predicted the future present.
Underground is a competent player's manual with a lot of colorful artwork and explanations. The detail that went into making the world come alive is unparalleled by most RPGs of it's ilk. Unfortunately, clunky mechanics and convoluted rules mar what could have been an awesome game. When played, my party spent most of the time distracted by the math and trying to figure out the combat system, which is straightforward but lacks the smoothness of a Dungeons & Dragons or Pathfinder related system. Still, it's a decent game if you're into Mayfair's game system and mechanics and like really in-depth character creation and modification. If you're looking to just pick it up and roll, I'd look elsewhere.
If you've read the graphic novel Marshal Law or seen Aeon Flux, you've had a taste of what sort of world Underground presents. The characters are genetically modified ("boosted") veterans that have been dumped on the streets of 2021 America that is a biting parody of modern politics and life in the U.S. Back in 1993 when it first came out, a lot of people didn't really know what to make of it. But it is actually quite playable and if you're in the mood for some gonzo, post-modern, de-constructionist superhero gaming (yikes!) this is the game for you.