The second is almost more loyal than the first. In my opinion, the second one has the most free pens.
The first and second books can be said to have faithfully restored the original works, and they can also be said to be quite satisfactory. The third film was directed by the famous Alfonso Cuarón, who made many bold adaptations that I found unacceptable at that time.
This is the first film that is not completely loyal to the original, so it can be said that it is full of controversy (at that time, now I believe that most people think this film is the best), and a lot of details of the original film have been deleted (for example, opening the gift box at Christmas, many small things in Crook Mountain, etc.). ).
There is an extremely important change in the setting of the third film: the protagonists no longer wear school uniforms and robes. This setting continues until the end. I still can't figure out why I'm so disloyal to the original. Is it to highlight the protagonist in the camera? Is it for commercial breaks? Or did the whole crew forget?
So the first part, the second part is relatively complete, and the third part is a failure.