Reading the Harry Potter books as they were published, with two or three year gaps between each (and with the films already being made of the earlier novels as the later novels were being published) was a great, collective experience. I can remember telling my sons on the night Deathly Hallows was published, a night of absurd media over-reaction, that they should savour the moment, because no-one was ever going to be able to read Deathly Hallows for the first time ever again – every subsequent reading of any of the novels would be in a world where the ending of the series was known.

Speculation prior to the novel being published as to the identity of the Half Blood Prince (once the title had been confirmed, which was a media event all of its own) was rife. The revelation at the novel’s climax shows that Rowling once again set her readers a puzzle that they could not reasonably have been expected to solve – we are never told that Snape is a half blood nor that his mother’s maiden name is Prince, and while both are guessable, that’s not really the way literary puzzles work is it? Similarly futile speculation surrounded the book cover imagery when it was revealed – what are Harry and Dumbledore doing?

When chapters of the Harry Potter series break away from the concentrated focus of the central character, readers know to pay particular attention. These chapters are few and far across the seven novels – arguably there is only one other outside Half Blood Prince, the opening scenes of the Philosopher’s Stone, following Vernon Dudley to work (the opening scenes of Goblet of Fire, in which the caretaker Frank Bryce is murdered, is later shown to be Harry’s dream/vision). So the initial chapters of Half Blood Prince stand out. The first – The Other Minister – is a comic scene which could have been included in almost any one of the preceding novels. The Minister for Magic pays an impromptu visit to the British Prime Minister to brief him on the disturbing developments in the wizarding world. The second chapter is far more significant for the plot arc of the series. Narcissa Malfoy, Draco’s mother, and her sister Bellatrix Lestrange, pay a visit to Spinner’s End, the bleak Northern city which is the out of term home to Severus Snape. (As an aside, I just wanted to say that some of the casting decisions in the films were debatable, but the actor playing Bella, Helena Bonham Carter, was brilliantly cast). Despite Bellatrix’s opposition, Narcissa begs Snape to help Draco in the mysterious task he has been given by Voldemort. Snape is cross-examined by the sceptical Bellatrix, and explains his role as a double agent within Hogwarts and the Order of the Phoenix. Snape makes an Unbreakable Vow, swearing to assist Draco and if necessary complete the task he has been given should he fail. The detailed wording of this Vow was pored over by readers at the end of Half Blood Prince, trying to understand Snape’s true role in the conspiracy against Dumbledore.

Harry’s storyline in the novel opens when Dumbledore arrives at the Dursleys to escort him to the Burrow, home of the Weasley clan. On the way they take a detour to meet Horace Slughorn, a former Potions teacher, where Dumbledore not so subtly uses Harry’s notoriety to persuade Slughorn to return to Hogwarts. Dumbledore also tells Harry that this year he will be giving him private tuition. It is these ‘lessons’ (although they can only be thought of as lessons in the loosest terms) that form the spine of the novel. In them Dumbledore shows Harry a collection of memories he has collected in his research into the life and times of Tom Riddle, starting with a disturbing visit to the Gaunt family home (again notionally a non-Harry chapter, although seen by him in the Pensieve). Outside the Potterverse Dumbledore could have told Harry these anecdotes and explained their significance in an afternoon, but the demands of the narrative require them to be spread out across a whole school year (Harry recaps the scenes to Ron and Hermione fairly quickly after each ‘lesson’ without too many complications.)

There are several other threads to the novel in addition to the slow reveal of Voldemort’s plans. The discovery of an old annotated potions textbook, previously owned by ‘the Half Blood Prince’, allows Harry to excel at potions, taught this year by Slughorn, Snape having finally secured the Defence Against the Dark Arts post. His new-found brilliance at potions allows Harry to win a bottle of Felix Felicis, so called “Liquid Luck”. Another thread is Harry’s strong suspicion that Malfoy is now a death eater and is working on a task set for him by Voldemort. He trails him using the Marauders’ Map, without success. Meanwhile the romantic storylines that have been brewing throughout the series start to come to fruition, with Ron and Hermione growing closer despite Ron’s comically inept romance with Lavender Brown. Harry’s feelings for Ginny are also growing harder to deny.

Finally, the secret that Dumbledore has been edging towards all year is revealed – Voldemort has created six horcruxes, magical objects containing a portion of his soul. Only if these artefacts are destroyed will Voldemort become mortal. We later find out that Dumbledore reveals this information to Harry alone (rather than telling his trusted allies in the Order of the Phoenix) on the tenuous grounds that he wants to ensure Voldemort doesn’t realise his horcruxes are under threat and take steps to protect them. Voldemort’s vanity is his fatal flaw – instead of just using a pebble on a beach, his horcruxes are valueable, significant objects that have a connection to the founders of Hogwarts. Harry and Dumbledore apparate (alone? Why no magical escort, guards, weapons!) to a sinister seaside cave to retrieve a Horcrux. The novel’s sustained climax is well known, but I will avoid pointless spoilers – suffice to say the adventure and excitement in the novel are at a different level from Order of the Phoenix (saving its final chapters in the Department of Mysteries). Schoolwork is relegated to its correct place.

Half Blood Prince is a well constructed adventure story where dark magic takes centre stage. The central and supporting characters are all now very well established, and Rowling’s world-building begins to pay off – we really feel as if we are inhabiting a complete world. New additions to the Potterverse, such as liquid luck, horcruxes, and spells such as sectumsempra are all inspired, and the revelations about Harry and Voldemort’s past begin to throw the earlier novels in the series into a new and darker light. The pieces are now all in place for the series’ astonishing climax. Lucky readers that can now read the whole series without the suspenseful two year waits!