While 21st Century Fox (FOX) has been getting some attention for its upcoming "Gotham" TV series (based on DC Comics' "Batman" universe), Fox isn't the only company that has licensed DC Comics characters from Time Warner's (TWX) Warner Bros. studio. Comcast's (CMCSA 0.15%) NBC is also developing a series based on a DC Comics property: John Constantine, star of the "Hellblazer" comic.

The character's story was adapted in 2005 by Warner Bros. as a feature-length film starring Keanu Reeves, though the film made several departures from the comics it was based on. Among these departures were changes to John Constantine himself, with the blonde Englishman becoming a dark-haired American who lost his trademark cockiness and gained a new origin in which he was damned due to a previous suicide attempt. For NBC's series, Constantine is supposedly getting back to his roots; to help with this, the network has cast Welsh actor Matt Ryan as the titular supernatural detective.

So who is John Constantine?
Assuming that the pilot (written by David S. Goyer and Daniel Cerone of "Dexter" and "The Mentalist") follows the comics as closely as it's rumored to, there are a few things that we can determine about the lead character and the direction that the series will take.

John Constantine is an occult detective whose family had been cursed with the gift of magic. Mastering the magic at a young age, Constantine lets his ego get the better of him and pays a massive price: during an exorcism gone horribly wrong, the soul of the girl he was trying to save is lost to Hell. Because it was his fault, his own soul is damned in the process. This doesn't drive him to a pious life, however; despite genuinely trying to make amends and help others in need, he is a hedonist who smokes, drinks, and tries to enjoy as much of life as he can before he's condemned to the flames.

The official synopsis of the pilot mentions that Constantine is "haunted by the sins of his past," suggesting that at least some of this origin will remain intact. He will be attempting to save the daughter of a late friend who has been targeted by a group of demons, which may also serve as a parallel to the tragedy of the failed exorcism.

Will this tie in to the DC Comics universe?
It's unlikely that there will be any connection to the mainstream DC Comics universe, but that's not entirely unexpected. "Hellblazer" was published by DC's "Vertigo" imprint, setting it apart from the reality shared by most of DC's characters. The character of John Constantine was incorporated into the main DC universe as part of the "New 52" initiative, increasing the likelihood of him teaming up with other popular characters. For the NBC series, however, it's likely that the network only licensed the core "Constantine" characters. This isn't necessarily a bad thing, however.

"Hellblazer" was the longest-running series of the "Vertigo" imprint, reaching issue 300 before being cancelled to integrate Constantine into the New 52. This gives the new series a lot of existing material and characters to work from, in addition to the inevitable "made for TV" characters that will appear. While it might be a nice nod to DC Comics fans to see references to Wayne Enterprises or meet characters named after superhero alter-egos, these appearances might seem a little out of place given how much of the character's backstory was separate from the main DC continuity.

A hit series in the making?
While fan reactions concerning "Gotham" have been mixed (though seem to be improving with each casting announcement), "Constantine" isn't likely to face the same scrutiny. Many of the criticisms surrounding "Gotham" deal with the show taking place before Bruce Wayne became Batman, leading some to complain that they aren't interested in a "Batman" story without Batman. "Constantine" won't have this problem as it's focused squarely on the lead character of the comics.

At this point, the likelihood of the pilot being picked up for a series is pretty high. Provided that director Neil Marshall (director of The Descent and episodes of "Black Sails" and "Game of Thrones") can set the right tone, "Constantine" may provide viewers with an experience unlike anything else that's on TV. Mixing magic and the occult with an intelligent (if snarky) detective who's weighed down by the sins of his past could conjure up another hit series for NBC.