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First I have to say I've never read the comics, so I can't compare the movie to them. Next, I should say the vampire mythology here isn't quite what I'm used to. I'm okay with each mythology making its own claims about certain things concerning vampires, such as abilities and weaknesses. But I'm pretty much used to knowing, more or less universally, that the only way for a vampire to come into being is for a human to be turned by another vampire. However, the main villain in this movie is Deacon Frost, who seems to be considered inferior by this council of pureblood vampires, because he was turned from a human. The council were all born as vampires, and I'm not really used to the idea that vampires are capable of reproducing in such a way. Except, of course, for certain mythologies which hold that a vampire and a human may procreate a half-breed, or dhampir (though obviously that says nothing about two vampires reproducing). And, one might call the hero of the movie, Blade, a dhampir... except that he wasn't created in this method. Rather, a vampire bit his mother while she was pregnant, and that transformed Blade's DNA, so he was born half vampire. He has all of their strengths, but none of their weaknesses, except the need for blood. Oh, and he ages as a human rather than a vampire.
Anyway, when Blade was 13, living on the streets, he was taken in by a vampire hunter named Whistler, who developed a serum to inject him with on a regular basis, so that he wouldn't need to drink blood. He also creates weapons, which the two of them use to hunt vampires. The movie begins, however (after the brief initial scene of Blade being born and his mother dying), with Blade as an adult, busting up a vampire night club rave style o' fing. One of them is Quinn, who works for Deacon. Quinn ends up nearly killed, burnt apparently to death, so he's sent to the morgue or whatever. But then he comes back to life and attacks a couple of the pathologists there, one of whom is Dr. Karen Jenson. Blade shows up to finish Quinn off, but fails, and when the authorities show up, Blade leaves, taking Karen with him. Whistler fixes her up, but she only has a matter of days before she would become a vampire, herself. So she tries to develop a cure.
Meanwhile, Deacon is having trouble with the council. But that's of little concern to him. He has big plans, which involve translating ancient texts that no one but him (and his followers) seems to believe in anymore. He wants to resurrect a vampire blood god called La Magra. And um... I dunno what else to say. Plenty of cool music and battle scenes and whatnot. Decent enough story. Um... yep, that's about it. Definitely a fun movie, I guess. And there are a couple of sequels, which I'd probably like to see sometime.