A Song of Ice and Fire, book 5
by George R.R. Martin
This book is in many ways more of a companion than a sequel to book 4. The storyline overlaps quite a bit. However, this book covers more time than book 4 does and ends at the beginning of winter. This book covers Tyrion, Jon, Daenerys in great detail. Bran and Davos also get a few chapters, but we're kind of left hanging about what exactly is going on with them. Characters from book 4 also re-emerge. We do find out what happens to Cersei and Arya, and we get a glimpse of Jaime. However, we are still left hanging as to what happens to Sansa and Brienne of Tarth.
A few other characters reappear or are introduced for the first time. I had thought Theon was dead, but apparently not. Unless Martin describes a corpse, you should not assume someone is dead. Victarion Greyjoy, Quentyn Martell, and Ser Barristan Selmy also contribute. A new, very important player in the game of thrones is also introduced, but his perspective is not shown. I'm now not so confident about who is going to win the game. My bets were on Daenerys, but this new player has definitely thrown a wrench in that plan, especially since Daenerys is barren.