Every Harry Potter Book Ranked From Worst To Best

4. The Half-Blood Prince

By the penultimate book of the series, we were a world away from that wondrous beginning and instead plunged into a far darker, more adult story - a wise move, because readers grow-up alongside Harry.

To that end, The Half-Blood Prince is the darkest of the lot, as you might expect from the book where Albus Dumbledore dies. That death is a hugely powerful moment, but it works so well because of the build-up to it. It's that relationship between Harry and Dumbledore, with the two of them working together in a way readers had long hoped for (especially after the distance in book 5), that this novel excels at.

Through that we get another of its strengths: the backstory of Tom Riddle, which sheds key light on the man (and boy) who would become Lord Voldemort. The final third is an utter thrill, with the hunt for the Horcruxes firmly on, and the cave sequence is one of the most exciting and very best in the entire series. The identity of the Half-Blood Prince is another example of Rowling's ability to craft a mystery, and one with a game-changing payoff. The darkness is somewhat balanced by the prominence of Quidditch too, with Ron getting his turn in the spotlight and adding a bit of levity to proceedings.

It does, however, feel a bit slow, with not a lot of moving parts as we delve into memories, meaning most of the action is packed into that final act. The relationship drama isn't the most interesting either ("Won-Won and Lav-Lav"), and a lot of what happens is just setup for the final book. But when that setup includes Voldemort's past and Snape's betrayal, it's easier to buy.