This had made into a movie (Brendan Fraiser) and I'd watched it a couple of years ago, so unfortunately for me I had all of the actors' faces in mind throughout the book and left little to my imagination there, but at least they casted it very well!!(and closely to the book's description - for the most part.
The PLOT deviates some, so even if you've seen the movie, you'd be missing out not reading Funke's wonderful writing
You get the plot from other reviews', so I will leave you with this. There are NOT too many books of this genre that are truly original. This is. There are not too many books out there that don't fall into some campy dialogue. This doesn't.
I go through books, Kindle and otherwise, and after reading Inkheart, I went and purchased the trilogy hardcopy (of which I'm terribly discerning about what takes up space) because I think this is a classic.
My son just read it as well, he's 8, but reading beyond his 2nd grade level, he finished and immediately asked when he's getting the next one!! And has asked me twice, "Is it here yet?"
I think it's a testament to Funke's writing, that she can so capture myself and my son so completely.