At this point most of the magical world has chosen not to believe Harry or Dumbledore about the resurrection of Voldemort, instead seeing them as delusional. Harry even has to deal with schoolmates who don’t believe in him anymore. What’s worse is that the Ministry of Magic, one of the leaders in the disbelief against Voldemort scheme is taking a hand at Hogwarts, sending in a Defense Against the Dark Arts who is both nauseatingly sweet and maniacal at the same time.
Each of the characters come into their own through this book, realizing that the threat of Voldemort means that they have to learn to protect themselves, no matter the cost. Slowly the rest of Harry’s friends, old and new, realize the threat and work to create a defensive group to learn the skills they need.
The end of the book shows the power of friendship, as well as the strength of prophecy, love, and revenge. There is a climactic battle between Harry and his friends along with the Order of the Phoenix and Voldemort’s strengthened band of Death Eaters.