It was also turned into an anime under the title Grey: Digital Target.
The world is covered in wastelands that are dotted with numbered "Towns." All Towns are supervised by computers called "Little Mamas" (nodes connected to the world governing super-computer called "Big Mama"); the underprivileged live in the slums and are referred to as "People." One can only become one of the privileged "Citizens" by joining the army and fighting the other Towns' forces, as the Towns are continually at war with one another. Combatants earn 50 credits per mission, plus 30 credits for every enemy killed. Once the total reaches 1000, the fighter's class is increased by one category (starting at F, then going to E, D, C, B and making one's way up to A). The A class guarantees a transfer to the idyllic, legendary "City."
Citizens have numerous advantages over People: in addition to getting out of the ghetto, they do not worry about being beaten up, raped or otherwise victimized. It's this advantage that leads Grey's lover, a girl known as "Lips," to become a Citizen. Her death leads Grey to join the army as well and follow her dream of getting to the City by sheer force of will. Grey soon earns the nickname "Grey Death" for his tenacity on the battlefield and ability to survive when the rest of his comrades are killed. He only accepts orders that keep him alive, and will not kill the resistance fighters that fight against the Town system because they are not worth any points. Sullen and cocky, Grey exists only to survive and kill, in that order.
Grey's sense of loyalty gets him into trouble when he finds out that his field commander, a man that saved his life many times, is lost in the African sector. He abandons Town 303 to go look for him. Along the way, he discovers who and what the resistance fighters are, why the Towns are all different in both military might and how they are run, and what the true secret of "Big Mama" is.
Grey is not a lighthearted adventure. The nickname of "Grey Death" is accurate, and the bad luck Grey seems to spread around makes his tragic situation even worse. As we follow him through his adventures, things get darker and darker.
Grey consistently encounters "dolls" (robots and androids closely resembling humans in behavior and speech), leading to tension between his search for the truth behind the Little Mamas and his reliance on robots to perform menial tasks.
Yoshihisa Tagami draws detailed vehicles and mecha in a variety of styles and a mix of retro and future weapon technologies. Each chapter adds new mecha or fantastic weapon of destruction. Towns have different tech levels: we see World War II style tanks, Grey's signature attack jeep, advanced F-15 style jet fighters and other realistic machinery. The series also features armored suits, jet bikes, walker style mecha and cyborgs. The series is notable for the Maya and Inca feel to the technology seen in the latter chapters.
Tagami's characters are simplistically rendered, especially with regard to their facial features. Some of the characters look a little stereotypical of the character design style that stuck around throughout the 1980s.