The father of Sam and one of the most fearsome and respected warriors in all of Westeros, Randyll Tarly is almost certain to show up in season 6, and is a very good bet for the character McShane will be playing. In his 50s-60s, the age fits, and from what we know of the character he'd definitely be a good fit as an actor as well, bringing with him an air of intimidation that is key to the part. He hasn't appeared much in the books as yet, but with Sam heading to Oldtown, and Euron launching an attack on the Reach, then he should be set to come into play a little bit more, and that figures with the 'small' description of McShane's character. Furthermore, he wields a sword made of Valyrian steel, and as witnessed last year that is a pretty important weapon to have. In the books he has now reached King's Landing, which may be a route they go down in the show - although that takes him away from Sam, and the prospect of McShane giving his son a dressing down is an enticing one - and he'd just as easily fit in perfectly as a no-nonsense member of the King's Council. Whatever they do with the character he should be entertaining to watch, and McShane does seem perfect for the part. He's said to be involved in the story of a central protagonist (which indicates Sam/Oldtown rather than King's Landing) and would mean it could still be a small role, but a very important one as well.
NCTJ-qualified journalist. Most definitely not a racing driver. Drink too much tea; eat too much peanut butter; watch too much TV. Sadly only the latter paying off so far.
A mix of wise-old man in a young man's body with a child-like wonder about him and a great otherworldly sensibility.
