I can remember finishing Goblet and being aghast and wanting to read the sequel immediately. We had to wait the best part of two years before we got it. And then it was weird. Harry was not the Harry I remembered. He’d gotten really surly and quite mean and it took me a fair few chapters to get used to this new aggressive and angry Harry. In addition this is the book where Dumbledore lets the reader down and we become as frustrated as Harry because he isn’t there and when he is he’s aloof.
And then we come to Delores Umbridge. She has to be in the running for one of the most odious characters in the entirety of the Potterverse. Vile, bigoted and driven. She is insidious in her attempts to control Hogwarts. Her detention quill is a very nasty piece of equipment and despite not being allied with the Death Eaters she’s a hideous character.
This is the novel where things really start getting darker: Harrry’s visions in his dreams. Dumbledore’s Army. Harry learning that his Father wasn’t really the person who he thought he was, at least not at 15. And Snape, this is where we understand him so much better than we have previously.
Also this is by some considerable way the longest of the books. Wish me luck.