If you're looking for a full-fledged fast-paced non-stop adrenaline pumped action anime (comparable to action movies like Die Hard or Crank (not story wise or anything just pace-ish)). Then you can stop looking, this is it, the ultimate action anime. Badass protagonists, lots BIG guns, wannabe super-villains who get their asses kicked, zombies, vampires, nazis (possibly a Indiana Jones homage, lol?) and spice it up with a little humor between the action scenes (are there other kind of scenes in this anime?).
Great, if you're looking for an anime for entertainment and willing to overlook the fact that there is no character progression at all and that the story is horrible. Basicly they skipped the story and extracted (and greatly improved) only the action scenes from Hellsing TV, later on it starts to shoot off though, but the story is still tremendously bad. It completely lacked lacked the criterias for a "superb" or "masterpiece" anime, that is in my educated opinion; thought-provoking, plot- or character-driven anime. But it wasn't trying to be anything like that. This anime is none other than pure entertainment. So shut off your brain and enjoy.