Harry Potter and the Order of the Phoenix.

Harry Potter and the Order of the Phoenix, more than any of the four previous novels in the series, is a coming-of-age story. Harry faces the thorny transition into adulthood, when adult heroes are revealed to be fallible, and matters that seemed black-and-white suddenly come out in shades of gray. Gone is the wide-eyed innocent, the whiz kid of Sorcerer's Stone. Here we have an adolescent who's sometimes sullen, often confused, and always self-questioning. Confronting death again, as well as a startling prophecy, Harry ends his year at Hogwarts exhausted and pensive. "The Order of the Phoenix starts slow, gathers speed and then skateboards, with somersaults, to its furious conclusion....As Harry gets older, Rowling gets better." (John Leonard, The New York Times). It was made into the 2007 film directed by David Yates, starring Daniel Radcliffe as Harry Potter, alongside Rupert Grint and Emma Watson as Harry's best friends Ron Weasley and Hermione Granger.