A Storm of Swords is the book that Game of Thrones seasons three and four were based on and it's the overwhelming fan favourite out of the A Song of Ice and Fire series. I'm not sure if it would be my personal favourite though. I think my favourite in the series is still A Game of Thrones but I only like it slightly more than this one. That book contains plenty of backstory and historical information but it still manages to be a brisk and fast-paced read. I found all of the different storylines in that book extremely interesting and not once did it drag for me. Also, when you know of all the tragic things that will later happen to the Starks it's so nice to go back and revisit the scenes where they're all together and happy! And alive! :) I found the pacing in A Storm of Swords to be a bit too slow at the start and there were a couple of storylines that I struggled with. For example: I'm still not a fan of Davos and I found Arya's storyline quite draggy and repetitive in this one, which really surprised me because her storyline in A Clash of Kings was tied with Tyrion's as being my favourite. Her scenes with Jaqen H'ghar in that book are awesome and I'm really hoping that he'll come back into the series at some point.
These minor things aside, A Storm of Swords is still a brilliant book and I continue to be blown away by the world and characters that George R.R. Martin has created. This book is a true epic and a massive gamechanger novel. It expands the story in so many different ways and so much happens in it! Although I did find the book a bit slow-paced at the start, once it gets going it becomes a truly gripping read. There are so many thrilling and suspenseful scenes in this book, so many twists and turns. We get the Red Wedding, the Purple Wedding, Sansa's escape from King's Landing, the Battle at the Wall, Tyrion's trial, the Mountain vs the Red Viper, Dany's conquests of the Slaver's Bay cities, and Sansa's final chapter. The existing characters in the series change and develop so much in this book and we get some great new characters. I'm thinking of Oberyn Martell and Lady Olenna Tyrell, the Queen of Thorns.
I've decided not to comment on every single one of the character's storylines in these ASoIF reviews of mine, although maybe I'll do that at some point in the future when Martin eventually finishes his series. For now I'll just mention the POV characters that particularly grabbed my attention. In this book my absolute favourite POV characters were Jon Snow and Daenerys Targaryen. Their stories are full of action and drama, and they themselves get so many badass scenes and moments. I've become convinced that they're the major protagonists of A Song of Ice and Fire; that Jon represents the "ice" of the title and Dany the "fire". Jaime Lannister gets some terrific character development in this book as well. In A Game of Thrones Jaime seemed like a horrible person. He came across as cocky and smug and dreadfully immoral. But in this book Martin makes him a POV character and we get to understand Jaime more. We find out more about his backstory and how he views the world. We see him being humbled by the loss of his hand. On the inside, Jaime is actually a very different person to his father and sister. He really does have morals and a sense of honour. He has questionable morals and a complex sense of honour to be sure but, they're there! You can see that in his scenes with Brienne and during his final scene with Tyrion - which is so sad in the book :( I love a good redemption story and I really hope that Jaime finds his redemption by the end. Sansa's story becomes extremely gripping at the halfway point of this book as well, and I really enjoyed Bran and Tyrion's storylines.
Finishing A Storm of Swords was a bittersweet experience for me. From what I've gathered, no-one seems to think that the next two books in the ASoIaF are as good as the first three. I've heard that A Feast for Crows is a very Cersei heavy book, and that both A Feast for Crows and A Dance with Dragons are too slow-paced and introduce too many new characters. That's made me think that the series has peaked with A Storm of Swords which makes me sad, but I'm trying to ignore what I've heard about the next two books and go into them with an open mind.
P.S. A Storm of Swords is a huge book, so huge in fact that in the UK its paperback edition has been split into two separate volumes: Steel and Snow and Blood and Gold. I'm not sure how I feel about this. It makes the book much easier to carry around of course but you do pay more for it.