I've known how Patrick Donovan writes for years, now, after taking part in many a writing drill together. I've known he's got a knack for description and a keen eye for entertaining readers. When he told me he'd signed a book deal, I was pretty happy for him! I'm happier, still, that Demon Jack isn't some boiler-plate urban fantasy work - it's solid entertainment, and it's definitely worth a read.
Let's start with the great strength of this work, that being the characterization of our titular hobo, Jack. Jack is a jovial name; he is not a jovial fellow. It isn't a big shock that Jack signed a contract with a demon named Alice - we learn this pretty early on, in fact. Jack ends up "recruited" to a clique of characters who resemble a multi-faith, grim-faced Scooby Gang worth of demon-fighters. Of these, a powerful witch named Maggie serves as Jack's main point of contact, and she does a good job of not becoming that gorgeous and powerful female sidekick who loses every scrap of dignity after falling in love with the weird goth kid; the one with vicious scars all over his face who talks to demons, but really, deep-down just needs a bit of love. So, Jack and Maggie go on adventures, right? That's how these stories go, yeah? Well, Jack and Maggie live in a pretty dark world, and they have to deal with Jack's particularly unfortunate past. He's got vampire-boss gunning for him, and he ends up in a show-down against a literally biblical force of evil, so "adventures" is a pretty romantic term for it all. Jack doesn't have many good days, and even his good hours end up turning dour as his past sins kick his new friends - a young girl named Lucy, in particular - in the teeth quite regularly. Summed up, readers will find themselves loving to hate Jack, even if they don't exactly love him as a person (fictional). He's selfish, he makes bad decisions, and he's kind of a jerk; but he tries to earn a little redemption in between attempts to drown his sorrows, and one gets the impression that there's hope for him, yet.
The prose itself is strong. There are occasional editorial gaffes, but no editor is perfect. There's mountains of metaphor and the description of combat scenes are particularly well done; suitably gruesome for the tone of the world Jack inhabits, but not over-the-top, either. Dialogue exchanges are satisfying and to the point. Donovan went to fair lengths in researching biblical information to put his work together, but he doesn't limit the mysticism in his world - or the "righteousness" of faith - to the Judeo-Christian heritage. While there could perhaps be a bit more structure to the work, with regards to framing what is going on for the reader's understanding, we are ultimately restricted to Jack's point of view (good 'ol first-person-narration), so there's less opportunity for exposition. Overall, it works - and, as it leaves room for a sequel without bashing a reader over the head with the promise of one, chances are we'll find out more about Jack's world in due time; it does, after all, resonate with certain other worlds-which-are-dark, but it stands out all the same.
If I had to find a weakness (and, from a critical standpoint, I believe I have to), it's probably that Demon Jack doesn't directly attack larger literary themes on a regular basis. It is without question a great, fun book. You will read it in under a week because it is easily processed and incredibly entertaining! But, for example, Jack doesn't spend much time musing over the mysteries of the divine. For a man who sees demons on a regular basis, Jack certainly doesn't devote energy towards considering the "good" side of "good and evil," or the implications of solid evidence for religious faith. This certainly fits with Jack's character, and it fits with the world he lives in. He has too many things trying to kill him to worry about whether his soul is corrupt, or whether or not he can and will be redeemed. His mind is already made up on the first, anyway, and maybe that's okay. While an opportunity to explore morality may have been passed up on, the fact is that a great book doesn't have to address those things.
Sometimes, a great book just needs to be a great story, and that's what you'll get from Demon Jack.