The former Dr. Feelgood star, who has inoperable pancreatic cancer, made his acting debut playing mute executioner Ser Ilyn Payne, but he admits he had no idea just how successful the big-budget fantasy series was.
He tells Britain's Daily Mirror, "They said it was for an American Tv series and I thought it was going to be like Xena: Princess Warrior so I thought, 'I'd love a bit of that, at least I'll get a leather jacket out of it or something'.
"The first filming was in Ireland and I looked round and thought, 'B**ody hell, this is a proper job!' It was great fun. My character doesn't have a tongue so I didn't have to learn lines."