One of my New Year's resolutions is to not spend so much effort writing about general release movies. If there are more than 50 reviews on rottentomatoes.com, I'll assume you can get a plot synopsis elsewhere.
With that said, this movie is as good as the reviews would suggest (81% on the tomatometer, which is practically unheard of for a horror movie). Full of Spanish Gothic style, some genuine scares, and real pathos. The ads are a little disingenuous pushing it as a Guillermo Del Toro movie--he executive produced but didn't direct (J. A. Bayona does a fine job there). Fans showing up expecting a"Pan's Labyrinth" might be disappointed in the lack of freaky Del Toro-esque creatures (the trailer for "Hellboy 2" should get them excited), but they shouldn't be disappointed in either the story or the telling of it.