First of all, why is Vin Diesel the last witch hunter? It doesn't make any sense. There should be lots of witch hunters. It's not like the need for them died out. Sure, Diesel's Kaulder (K: the sexy new C) has been around since the Middle Ages, 'cuz a witch cursed him with immortality and stuff — bloody typical — but he was a witch hunter before that when he was still mortal. He doesn't have superpowers or anything. He's just a guy doing a job, and it's a job that still needs doing, even in the 21st century. Because even though there's a truce between witches and muggles (no one says "muggles," but you can hear them wanting to), there are some bad witches who break the truce and do bad things, like use magic when they shouldn't.
So. Wait. Hey. Why is Vin Diesel the last witch hunter? Witches aren't in hiding so that he has to hunt them down. They live out in the open, running nightclubs and flower shops. Really. He's more like a cop, investigating witchy crimes and putting the perps in jail. (There's totally a witch dungeon under St. Patrick's Cathedral! Or is that Grace Church in Greenwich Village? Or the Cathedral of Saint John the Divine way uptown? This sort of confusion is what happens when a film lets Pittsburgh stand in for New York. Now that's some evil we should be fighting.) His partner is a priest, played by Michael Caine until he smartly bows out of most of the film, and then he gets a new one played by Elijah Wood... and actually, if this were Law & Order: Black Magic it'd be a helluva lot more interesting than it is.
The Last Witch Hunter pits Diesel and his agonizing man-pain against the adherents of a long-dead Witch Queen (Julie Engelbrecht) Kaulder killed 800 years ago — or did he? dum dum DUM! — who might be trying to resurrect her in New York City so she can carry on being witchy. She doesn't like muggles, and brought the Black Plague way back in the day, because she is generally not nice. She has caused Kaulder much pain, so he shouts a lot and then goes quiet as he remembers how his wife and daughter died from the witch-brung sickness so long ago. So sad. Or so the movie would like us to believe. And then he growls something about how "for 800 years..." he's been doing something or other. And you may be tempted to help him finish his sentence by shouting out "have I taught Jedi!" But don't you mock his pain.
Or, go ahead and mock it, actually. It's the most entertainment you'll get here. The Last Witch Hunter is generic yet frenetic yet incoherent: You've seen this all before, and yet you still won't be able to tell what is allegedly happening onscreen when the hunters and the witches get into a rumble. CGI stands in for fight choreography, and hints about a potentially interesting subculture of witches living secretly among us go nowhere: Harry Potter this ain't. Mythic imagery is deployed in idiotic ways — the Tree of Knowledge, a.k.a. the Tree of Life, is not a symbol of evil, you production-designer twits — and clichés utterly fail to engage us emotionally: "This is not who you are," says someone who doesn't like what Kaulder is doing but who has no damn idea who Kaulder is because she only has just met him. "It's all I am," he replies. What is all he is? We haven't got the slightest clue.