1. Quirrell’s head

Aside from learning that Harry was a wizard, perhaps the biggest surprise from Philosopher’s Stone was the moment when Professor Quirrell peeled back his turban to reveal the leering face of Lord Voldemort. It was the first moment of real darkness in the series and it was creepy as heck.

2. I am Lord Voldemort

The apparition of Tom Marvolo Riddle was always a bit on the sinister side, but we weren’t prepared for the echo of this weird boy to turn out to be the younger form of the Dark Lord himself.

3. Sirius wasn’t a murderer

Finally, after months of mysterious sightings, tension and fear, a ragged, feral Sirius Black was at last cornered by the son of the friends he supposedly murdered – and not only was he actually innocent, it turned out that…

4. …Scabbers wasn’t a rat

Incredibly the Weasley family’s trusty, if strangely long-lived, animal companion Scabbers was not a humble rat. He was Peter Pettigrew, whom everyone believed to be a) dead and b) a hero. Wormtail, of course, was neither.

5. The Marauders

In a shock-packed chapter of Prisoner of Azkaban, we also discovered that the Marauders, Messers Moony, Wormtail, Padfoot and Prongs, were in fact Harry’s dad and his mates. It was almost too much to bear.

6. Cedric’s death

Now this was the moment when it all turned black; while darkness had been building throughout the books, and we’d seen or heard about the odd death, nothing could emotionally prepare the reader for the senseless death of such a good guy.

It all happened so suddenly. You were just as discombobulated as Harry and Cedric in that moonlit graveyard hundreds of miles from Hogwarts. It was a moment that just freezed your heart solid, as the golden boy was hit out of nowhere by the Killing Curse.

7. Voldemort reborn

Immediately after the emotional firestorm of Cedric’s sudden death, we didn’t get the chance to draw breath before we glimpsed the Dark Lord in a horrifying childlike state – and witnessed his sudden rebirth. Then the Death Eaters turned up and everyone tried to kill Harry and it didn’t let up for about 100 harrowing pages.

8. ‘Mad-Eye’s’ betrayal

The shocks didn’t stop when Harry made his escape. In the hullaballoo of his return he was abducted by an out-of-sorts Mad-Eye Moody. Who, of course, wasn’t what he seemed, and became roughly the twentieth person that day to try to kill our hero.

9. I must not tell lies

Harry was, admittedly, a little stroppy during his fifth year at Hogwarts, enough to exasperate even his most patient teachers. Still, the real shock came when we realised that Dolores Umbridge was far nastier than her pink outfits might suggest. Punishing Harry by forcing him to use a magic quill to write lines in his own blood was a bit on the drastic side.

10. Learning about Neville’s parents

Harry, Ron and Hermione bumped into Neville visiting his parents at St Mungo’s. The Longbottoms were tortured into madness by Death Eaters, including Bellatrix Lestrange. Neville’s mother wordlessly handed her son a crumpled-up sweet wrapper as a present, and then our hearts broke.

11. Sirius’s death

We all knew something bad would happen. Before Order of the Phoenix was even published, the death of a major, much-loved character was leaked to the press. But even then, Sirius’s abrupt death in battle, so soon after he’d regained his freedom and returned to Harry’s life, was wretched.

12. Snape was evil

From Harry’s point of view, former Death Eater Professor Snape had it in for him from his first year at Hogwarts. The Potions master was far from welcoming, and even seemed to be casting spells to try to knock Harry off his broom during a Quidditch match. It turned out that he wasn’t the culprit, but throughout Harry’s school years Snape was often scathing and hard to read. When he cast the Killing Curse on Dumbledore in Half-Blood Prince, it seemed that Snape had been working for Voldemort all along.

13. Snape was not evil

Perhaps the bigger shock, though, was the subsequent reveal that Snape was not in fact evil – he’d lived through a lot of hardship, anguish and hidden self-sacrifice. Everything fell into place after Harry browsed through his old adversary’s memories: James Potter was kind of a bully and Snape hated him partly because he was in love with Lily. He was also a double agent, even though he had at one stage been a Death Eater for real, the toe-rag.

14. Harry had to die

Possibly the biggest shock of all was that Dumbledore knew that Harry would have to make the ultimate sacrifice – and that he was so concerned to protect Harry not only because he felt the orphan deserved a good life, but because he knew that he would most likely have to die to defeat Voldemort.