It's no 'League of Extraordinary Gentlemen', by which I mean that it's good. Ron Perlman ended up being the perfect choice for the lead, and I am very glad that the director was dedicated to keeping this project true to the atmosphere and story of the source material and to his own vision. For example, he rejected suggestions for a helldog, a hellmobile, and that Hellboy be a regular guy who just turns red when he gets angry. Yes, these were serious suggestions from studio executives.
Mike Mignola, the creator of the Hellboy comic, mixes humor, black magic, the paranormal, and nazis. Fortunately, the emphasis on nazis isn't very strong, and the other elements combine with stylized and unique art to create fun, readable stories about a being from hell who's really a pretty regular guy. He happens to be big and red, largely indestructable, and fights monsters, but hey, that's no reason to be all broody and mysterious.
I'm not going to talk about the plot, for those of you who haven't seen the movie yet, but I will say that Hellboy's personality is perfectly captured, and in many scenes the movie comes as close to Mignola's stark artistic style as is possible in the real world. My husband complained on the way out of the theatre that there wasn't enough of the dark and creepy stuff that crops up in the Hellboy comic stories, until I reminded him of a few things. This is one of the strengths of the movie, that it mixes light humor with dark and disturbing images so well that it never precisely becomes horror but also is not gutted and inconsequential.
If you understand the construction of stories at all, some of the seams do show a bit. The POV character is obviously there for the viewers to identify with. As the 'new guy' he gets introduced to the other characters and the storyline along with the viewer, and we never learn that much about him, allowing us to more easily project onto his character. This really isn't a bad solution for making the story accessible to people who haven't read the comic, and is done fairly unobtrusively. The plot is tight, self-contained, and well-paced, the special effects are quite good, and there is action! romance! and humor! enough for all.
So, is this movie significant? No. Will it change your life? No. Will it give you a really fun two hours of entertainment? You bet.