At a Glance: Gungrave
Gungrave is a story by manga artist Yasuhiro Nightow, who also did Trigun. It was originally a video game for the Play Station 2, and the anime is based on the video game, which is in turn based on the manga. Viewers familiar with Trigun will notice the similarities, including a nearly invincible protagonist caught up in violent conflict he doesn't want to have a part in. Although, unlike Trigun, with its hippie-ish optimism and goofy comedy, Gungrave has an overall tone that is more brutal and serious.
manga by Yasuhiro Nightow
Definitely, I would recommend it for fans of more serious, violent anime, similar to Hellsing, Trigun, or Berserk. I thought each episode was interesting and compelling, and I wanted to watch more. The story starts in a present moment, but then everything that follows is one long flashback, showing how things got to that point. It's an innovative storytelling technique that got me interested in learning more about the characters' lives. It was interesting, it kept my attention, but I would have to watch the entire anime to see if it's something I would truly call great.