With a final “expelliarmus” this chest-crusher of a book ends the Harry Potter series with a bang, and the inevitable epic duel between good and evil. The fascination of the latest unfolding of J. K. Rowling’s work lies in the layers of grey that she reveals between dark and light. Characters are deeply probed and eviscerated, and even Dumbledore and Snape are not what they seemed previously. The plot — hatched over 17 years of writing — clicks into place, loose ends interlocking, all as complex as a magical lock at Hogwarts Castle.

Hogwarts, itself always a character, is almost sidelined until it becomes a backdrop for the final devastating battle. As Harry says, “This is war,” and Harry Potter and the Deathly Hallows is more of an outlaw adventure than a boarding-school tale.

The days of the simple pleasures of Bertie Bott’s Beans and the Weasley Twins’ Wizard Wheezes are forgotten, for these are dark and bloody times. Long-treasured characters die at the hands of Voldemort and his Death Eaters; schoolchildren are scarred; an ear is lost; and torture in the form of the gruesome Cruciatus curse becomes worryingly commonplace. This is by far the most adult of the books, perhaps reflecting our war-scarred times.

Following Harry's 17th birthday, and the end of the magical charm that protected him until his coming of wizard age, Ron, Hermione and Harry are on the run across England from the avenging Voldemort. You-Know-Who (and at last we discover a good reason for not using his name) has taken over the Ministry of Magic, and is crushing the opposition with an iron hand. Aided by the usual suspects — the Malfoys, Bellatrix, Umbridge, the persecutor-in-pink, plus posses of Dementors — Voldemort is also engaged in hunting down and destroying Mudbloods, those without magical parents.

There are all sorts of more sophisticated references here, from Arthurian to Greek myths. Shadows of the Holocaust hang over Voldemort’s compulsory Register of Muggle-Borns, the subsequent (Kafkaesque) trial and punishment of those with “contaminated” blood, and his decoration of the Ministry of Magic with a black statue of a pure-blood witch and wizard, atop a stone pile of the dead, naked bodies of Muggles.

All is not lost, however, and straightaway — for those of us speed-reading the book — the frontispiece quoting Aeschylus, the Greek playwright, offers a clue: It begins with “the grinding scream of death” and ends “bless the children, give them triumph now”.

The children are now really adults, but it seems strange that Harry is tall enough to bump his head on low ceilings and to receive a magic razor for his birthday, along with Ron’s present: “Twelve Fail-Safe Ways To Charm Witches”. Harry is so busy fighting evil that he hardly has time to reprise his panting pursuit of Ginny Weasley.

Harry goes on a quest to find and destroy the Horcruxes, objects that contain part of Voldemort’s soul, and also discovers the existence of the Deathly Hallows, three magical items that give power over death. Nothing is simple here, and indeed there are overlong passages, particularly those concerning Dumbledore’s past, that are a bit of a snooze unless you are a Potter-junkie.

The action scenes are fantastic, however, and the reader is aware that Rowling is writing with the big screen in mind. A panoramic battle in the night skies above 4 Privet Drive, in which Harry roars off on Hagrid’s motorbike pursued by Death Eaters, while magic spells flash by, will make a great opener in the final film. A fight with Voldermort’s snake-familiar, the anaconda-sized Nagini, will also look impressive in the cinema. Specialeffects departments will be celebrating the prodigious use of Polyjuice potion, which changes appearances instantly.

Much of the book takes place inside Harry/Voldemort’s head. The connection between the two becomes ever-stronger, as Harry grows wiser, and Voldemort more maniacal. Obviously we can discuss this no further in public: it is enough to say there seem to be two endings to the book.

The Deathly Hallows is a must-read, even for those who have not ploughed through every single novel in the series. Generation Potter — the children who grew up with the boy wizard — needs closure. Plus Rowling should be congratulated for her persistence, and for inadvertently doing more for literacy among schoolchildren than any government.

'I was weeping like a teenager'

When I was 15 and borrowing Harry Potter and the Philosopher’s Stone from my best friend’s little brother, I would no more have cried over it than I would have started a pension (Alice Fordham writes). But now, at 24, having waited years for this final book, I wept and laughed, and was truly stirred. As ever with Rowling, the real joy comes from the explanation of details you had forgotten from the previous books. Dumbledore’s brother and his fondness for goats become vital to the plot. Although minor criticisms will keep the chat rooms busy for years, this is a fine resolution.

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