For Harry’s sixth year, Hogwarts has both a new Defence Against the Darks Arts teacher and a new Potions master. The latter is Horace Slughorn, returned to Hogwarts after Dumbledore seeks Harry’s help in cajoling him out of retirement; for Slughorn has a carefully-buried secret that Dumbledore wants wormed out of him. He also has lower standard for his class, meaning that Harry and Ron unexpectedly find themselves eligible for N.E.W.T.-level Potions. Until they can acquire their own copies, he lends them old textbooks, and Harry discovers that his has been heavily annotated by a previous owner. The self-styled Half-Blood Prince had filled the margins with useful corrections and his own spells, both of which Harry cheerfully employs - to the horror of Hermione, who doesn’t trust the Prince, whoever he (or she) may have been. Nor does she trust Harry’s conclusions about the behaviour of Draco Malfoy. Sure, Draco’s unpleasant, but dangerous?
Spying on Draco, trying to trip up Slughorn, captaining the Gryffindor Quidditch team, learning to Apparate, following Dumbledore on a Pensieve tour through Voldemort’s past - it would be enough for anyone, even without the personal dramas. Harry and Hermione, Hermione and Ron, Ron and Ginny, Ginny and Dean, Dean and Ron, Ron and Lavender - with so many disputes, the Gryffindor common room is an uncomfortable place to be. Soon Dumbledore’s office is too, as Harry learns that destroying Voldemort is going to be far more difficult than he thought. The task gets even harder when the battle between good and evil breaks out again and changes everything.
After The Order of the Phoenix the series gets back to top form with the sixth instalment. There are still arguments aplenty, but here they have a strong element of comedy, rather than just teenage attitude and bad temper. Horace Slughorn makes a fine addition to the cast: self-important, elitist, name-dropping, and showing a different side to Slytherin house. It’s almost a mystery novel, with Draco obviously up to something, but no-one entirely sure what, and Harry taking every opportunity to investigate. The solution is clever, building on clues from previous books as well as this; and it arrives in a jaw-dropping, sit-bolt-upright ending. The stakes are raised and there is clearly no going back. Discovering the identity of the Half-Blood Prince is merely an added bonus.
The penultimate book in the series sets up what promises to be a stunning conclusion. Not just by the scale of the threat, but the size of the obstacles yet to be overcome. For Voldemort is no fool and ... well, let’s just say that there’s a reason the term ‘Death Eaters’ holds so much appeal. I picked up Deathly Hallows immediately after finishing Half-Blood Prince and can only imagine how much suspense the people who read the books as they came out must have been left in between the two.