Before I start, I will say that I found the movie to be somewhat entertaining, but I am not exactly sure how to rate it as an adaptation.
So, differences from the book. Well, there’s the matter that Tim Burton took the source material and changed it so that it would fit within one movie, whereas the original books were a trilogy. First of all, the main antagonist, Barron, is a complete fabrication of the movie. As far as I know the persona of Barron does not exist in the books, though some things from the book, such as Dr. Golan’s posing as the MC’s psychiatrist, are present. Overall the pace of the movie is massively sped up, given that it is shoved into one movie. Then there is the matter of the Hologhasts and the method by which they regain their humanity. In the books as I recall there was stuff about them stealing peculiar’s souls, whereas in the movie Tim Burton went for a a more Burton-esque method, where they eat Peculiar eyes. While the general concept of Peculiar Children is intact, Burton heavily changed the movie from the source material. However, I must say, regardless of whether or not it is book canon, the skeletons vs ghasts fight scene was pretty glorious to watch.
As to the actors. I loved the actors for this movie, they all did a good job of fitting Burton’s versions of the characters. Samuel L. Jackson was wonderful as Barron, as he usually is. The peculiar children’s actors were done quite well, none of them seemed particularly normal, and all of them seemed particularly peculiar. Enoch’s actor was creepy, as I would expect of someone who delights in corpses. The actor for Miss Peregrine did a good job. The actor for the MC was quite good as well, he did a good job of fitting the role of a character who, though he’s a misfit, is nowhere near as much a misfit as these peculiars. Sort of a normal misfit you could say. As to the father’s actor, he did a great job of making me despise him, which I suppose was the point. If I have any complaint it is that due to how compressed the movie is, and with how many characters there are, we don’t get very much characterization of these interesting characters.
So, all said and done, though I enjoyed it I can’t rightfully call this a good adaptation. However, since I found it to be an enjoyable experience I would personally put it in the ‘bad’ category rather than the ‘absolutely disgusting’. Though he did a bad job of following the books Burton did a good job of entertaining the viewer, and did a good job of creating interest in this book series so that people like me can bash the movie for not following the book. Entertaining movie, but not a good adaptation.