Owen Teale has revealed that people approach him on trains and beg him to abuse them in the style of his Game Of Thrones character.
The Welsh actor plays villain Ser Alliser Thorne in the HBO fantasy TV series, but said fans still warm to his alter ego.
He told Radio Times: "People love the character. They come up to me on the Tube and ask me to abuse them: 'Could you call me a 'bah-sted', I want to record it? Say it with real contempt'."
Owen said fans appreciate Ser Alliser is not just a panto villain.
He said: "He doesn't sit around cooking up evil plans. He thinks he knows what is right. His is a cynical, joyless version of the world - we are made from bad stuff."
The actor, 54, revealed that shooting in a quarry in the rain helps him find the darkness in his character.
"Castle Black is a permanent set filmed in this disused quarry not far from Belfast. And it rains and rains," he said.
"Once you're in the quarry you can't get to your comforts as an actor - to the caravans, to the food wagon; and they just keep you in there.
"When it rains it takes two people to put that enormous cloak on me and once it gets wet it probably weighs my own weight again, which is about 15 stone.
"So it's a bleak, horrible situation, often with me standing up to my ankles in water. But I think it helps. This is what Ser Alliser thinks the world is like."
Game Of Thrones has been a huge success critically and commercially, but Owen admitted he was not certain it would do so well.
"I didn't believe it would work in the beginning, anyway - I thought it was too unwieldy, too close on the heels of the Tolkien trilogy. But look how wrong I was," he said.
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