Characters will always be more engaging in books than in films

Here's why: Books don't have to describe anything literally.  Written stories can be filled with things like "his eyes were full of absolute fury" and "comprehension dawned on his face".

Many times even (or indeed, especially) in real life I have mistook someone's expression to mean something else.  You don't have to worry about this in books.  Everyone has their own ideas about how one ought to look when one is feeling a certain mood, and when the book describes the expression, the reader creates that perfect look in his imagination comfortably.  Thus, books are able to make use of complex expressions such as "he smiled, but the smile did not reach his eyes, which remained cold" and such.

In films, you gotta spell things out so vividly it can easily get awkward, just in case the audience doesn't understand what's going on! At least a live actor can do his thing, and see what happens, and maybe try again.  It's especially troubling in animated films, a slow process wherein waves of people can easily scrutinise every drawing, watering down expressions into clear, readable ones.