Not familiar with the comic, I found some background info on the comic on another Amazon review:
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Like a James Bond of the occult--only not as suave or debonair--Dylan Dog manages to get himself in and out of trouble with finesse, while bedding a different lady with each adventure he embarks on. A self-styled "nightmare investigator," he takes on cases that normal PIs won't. Along with his assistant, Felix, a quip-spouting Groucho Marx lookalike, he tracks down some extremely dark persons (and nonpersons) for a somewhat modest fee.
Dylan Dog was created by writer Tiziano Sclavi in 1986. Originally published in Italy, the long-running series is set in London, where Dylan works as a supernatural investigator who (against type in a series like this) has a good working relationship with the police. Dylan is a former Scotland Yard investigator, and perhaps the reincarnation of the original Dylan Dog, who died in 1686.
Dylan Dog's mysteries have been published off and on over the past two decades, with Sclavi backing off and allowing others to interpret the character. The good-looking investigator has become a true star in Italy's comics publishing, as well as around the world.
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This movie deviates from this description:
1) Dylan isn't a Casanova, he actually has some past that keeps him pushing women away
2) His sidekick looks nothing like Groucho and works for free vs. a fee. He does it more out a friendship for Dylan
3) No mention -- that I remember -- about his relation to Scotland Yard. His history and relationship to the undead/monsters is explained very differently in the movie.
4) No finesse in the movie...he is a "tough guy" instead who is willing to punch or shoot his way through to a solution
This movie actually starts off in a Dresden Files kind of way. . .
1) We have a broke Detective letting himself do work he'd rather not do just to pay the bills
2) He relies on "old" technology and the like
3) He has contacts all throughout the monster/undead community
4) A VW bug that isn't reliable
The funniest part of the movie is how his buddy/sidekick has to deal with his. . .uh. . .new condition. He's definitely the comic relief of the movie.
Brandon Routh has a great narration voice, just like the old detective movies. He's not required to do a lot of acting though. What would have made him more convincing is if they had made him all scruffy vs. his Superman, clean-shaven look.
The makeup job on the werewolves was kinda SyFy channel quality, but considering the movie it all fits
Taye Diggs had the best acting opportunities and he delivered them very well. Great job Taye.
There seemed to be something missing with the love interest in the movie...one minute they don't know each other the next its like she's giving him pity sex, because of his situation. I didn't get any chemistry between them. But when things heat up, his narration has a great one-liner.
What also didn't make sense, is the "monster" of the story kills people one way. But both times that Dylan comes-face to face with it, there is a punching match. Uh...why? Other than to extend the scene and give us some action, I guess. Inconsistent. Too bad. :(
The final transformation of the movie was cool.
Ending was okay...for me it was a bit anticlimatic, because it had nothing to do with the efforts of our main protagonist per se.
This won't create the cult following that Army of Darkness has.
But those wanting more of Dresden, and with none forthcoming, they may like to watch this for a lot of similarities.
And the name Dylan Dog just rolls off the tongue well. :)