In "Harry Potter and the Order of the Pheonix", Harry returns for his fifth year of study at Hogwarts only to discover that much of the wizarding community has been led to believe that a teenager's recent encounter with the evil Lord Voldemort is a lie, putting Harry's integrity in question. Worse, the Minister of Magic Arts teacher, the duplicitous Professor Dolores Umbridge. But Professor Umbridge's "ministry-approved" course of defensive magic leaves the young wizards woefully unprepared to defend themselves against the Dark forces threatening them, so at the prompting of his friends Hermione Granger and Ron Weasley, he is convinced to take things into his own hands. Meeting secretly with a small group of students who name themselves "Dumbledore's Army", Harry teaches them them how to defend themselves against the Dark Arts, preparing the courageous young wizards for the extraodinary battle that lies ahead.
The movie is very interesting and gripping, especially the part where Harry fights with Lord Voldemort together with Dumbledore. You should really see this gripping movie! :-)