Game Of Thrones Season 7: 10 Big Things We Still Haven't Seen

2. Jim Broadbent's Archmaester

As the series approaches its ultimate endgame, the focus is more on thinning the herd than swelling the ranks. There aren't too many new additions for Season 7, save for some cameos, but the biggest newcomer is Jim Broadbent.

His role was initially a mystery, before it was revealed by the man himself that he was - as suspected - playing an Archmaester. That pretty much confirms he is playing Archmaester Marwyn, aka Marwyn the Mage, a character Sam meets at the Citadel.

It's an exciting prospect, both because Broadbent is a wonderful actor with form playing "old professor types", and Marwyn is one of the more enigmatic characters from recent ASOIAF novels who could hold some key information.

The powers-that-HBO are keeping him under wraps, even though we know who his character is, but it should make for a great arrival in the show, and hopefully add some extra meat to Sam's storyline.