Game of Thrones will reportedly be sourcing a lot of material from the fourth book, A Feast of Crows, on the upcoming sixth season.
According to Watchers on the Wall, Clive Russell will return to play Brynden Tully, aka The Blackfish, whom we haven't seen since the Red Wedding in Season 3. The Blackfish will reportedly be defending Riverrun from a Lannister siege, including none other than Jaime Lannister (Nikolaj Coster-Waldau).
Jaime's journey into the Riverlands was a huge part of George R.R. Martin's book series, which is why many fans were shocked to see him travel to Dorne last season instead. But unlike in the books, Jaime will now be accompanied by Bronn (Jerome Flynn).
It's possible that the siege of Riverrun will also open up opportunities for the return of Edmure Tully (Tobias Menzies), who was taken captive during the Red Wedding by the Freys, the house that now looks to take over Catelyn Stark's (Michelle Fairly) first home. And since the North always remembers, this might mean fans can finally expect to see Lady Stoneheart.
Once resurrected in the books, the zombified version of Catelyn Stark leads the Brotherhood Without Banners across the lands, hanging those whom Lady Stoneheart believes wronged her - most notably the Freys, Boltons and, of course, the Lannisters.
Jaime best watch his back.