Matters converge: a final stand at Hogwarts against Voldemort. The last part of the eight-film cycle delivers in terms of epic action sequences, resolutions for characters followed over multiple movies, and a decent coda; no real surprises, and nothing for outsiders, which is perhaps as it should be.
Battle lines are drawn between Voldemort’s followers and others; Harry’s studies are supported by a mysterious textbook. Decent series entry, concerned with putting pieces in place for the final conflict. Not really a stand-alone movie, but series fans won’t mind that at all.
Voldemort’s rise develops; a fightback begins. Middling fifth instalment treading water between the establishment of the nemesis as a real threat, and its crystallisation; meanwhile, Hogwarts is put into special measures. Okay for fans, and well-enough done, but no classic.
Harry is mysteriously selected to take part in a wizarding tournament at Hogwarts. Fourth and perhaps the best of the sequence, balancing a stand-alone story with the developing Voldemort narrative. Little for series entrants, but a confident and well-made movie for fans of the books and the films to date.
Potter is threatened by a notorious escaped prisoner and ally of the Dark Lord. The third in the sequence is a touch darker, expanding the movie universe away from the quest-based adventures of parts 1 and 2. A step up all around, with confident direction, better effects, and actors maturing into their roles.
Harry and friends search for a hidden part of Hogwarts. Second and perhaps the least of the Rowling adaptations, this mimics the structure of the first, though adds enough novelty to please fans, and begins to develop the series mythology.