
Hellblazer was one of the most beloved comics that DC Vertigo published. It was never a huge seller, but it was consistently popular for 300 issues and, along with the title it spun out of, Swamp Thing, helped pave the way for mainstream comics aimed at an adult audience. It's one of my personal favourites, and like so much of Vertigo's early output, it's a great example of how to do horror well in comics.
One of the best things about Hellblazer was that, while it was technically set in the DC Universe, it was for all intents and purposes completely separate. It took the weird little occult corner established by Swamp Thing and walled it off from the rest of the universe, and as a result it took place in a world that was clearly meant to be - and was recognisably - our own. It was frequently satirical and blackly funny, with the third issue featuring demonic yuppies who were huge fans of Margaret Thatcher.

And what a character Constantine is. Blue-collar mage, silver-tongued conman, sneering punk - absolute bastard. He is, for want of a better way of expressing it, a startlingly human character compared to his demigod peers in the main DC Universe. Like so many of us, he tries to do the right thing but tends to take the easy, lazy decision which gets other people hurt. He's selfish and arrogant, and can treat even his friends pretty awfully at times - and there's no surer way to die in Hellblazer than by being friends with John Constantine.
He helped defeat the Original Darkness in the pages of Swamp Thing, and in his own title he's gone up against the demon lord Nergal, the hunger entity Mnemoth, and the First Of The Fallen, who became ruler of Hell after Lucifer quit in Sandman. But the evils he fights are often far more intimately connected with our reality, and are much more frightening for it.
In one of the all-time classic stories, Dangerous Habits, he contracted terminal lung cancer because of his twenty-a-day smoking habit. To quote the man himself: "I should die as I lived. Someday I would push it too far. Get too clever. The jaws of Hell would snap shut and for once I'd be that little bit too slow. My death would be unique." As an ordinary man, he's subject to all the everyday misfortune that befalls all ordinary people, and dying of cancer is the sort of fear that everyone can understand and relate to. We don't know what it's like to fight the hordes of Hell, but we do know what it's like to have to sit powerlessly by while someone close to us suffers from an illness they can't do anything about.

To Jamie Delano, the first to write Hellblazer, perhaps the greatest horror of them all is war, which he explored in his spectacular, fiercely angry original graphic novel Pandemonium. The book sees John coerced into going to Iraq and experiencing man's inhumanity to man first hand: demons are involved in the war and are profiting from all the death, but it's the actions of the humans involved in the conflict that are truly despicable. John gets arrested, beaten, and forced to go to Iraq on trumped-up charges by the anti-terror squad, for whose methods Delano clearly has nothing more than seething contempt. Once John arrives on the front line he sees prisoners being tortured for information and people who have surrendered being summarily executed: Nergal is doing well out of the war, but it's us who caused it. The real horror is that it's our fault: "we have the choice who leads us, apathetic, into pandemonium."
Hellblazer was cancelled last year in order to re-integrate John Constantine into the DC Universe, making him part of a world where super powered men in capes soar through the air and the mundane doesn't exist. It's an ill fit for a character so perfectly tailored to exist in our world, but Vertigo are currently publishing a new series of books which will, for the first time, collect every issue of Hellblazer in paperback. If you want to see how to take the everyday, which is paradoxically rare in comics, and make it truly frightening, you really ought to be reading Hellblazer.