Hellboy wasn't bad necessarily, but also not the best. Overall I did enjoy this movie and wouldn't mind watching it again. I enjoy gory and action packed movies, and this was definitely one of them. There was a lack of background stories to some of the characters, and too many different plots.
Also do not watch this if you can't handle gore, because this is one of the goriest movies I've seen yet. I am surprised though, that there wasn't a lot of swearing in the movie(kinda glad about it). You'd expect there to be, but there isn't.
Overall, I'd give it a 6,5/10