"I can't say anything about the character I'm playing," the Irish actor told UPI in a recent phone interview.
"It's just like the 'Game of Thrones' thing -- 'Don't talk about it.' But this new character is coming into the 'Peaky Blinders' world and I've been asked not to say anything about it."
"I suppose the new development in that is that Adrien Brody joined and Charlie Murphy, a great actress from Dublin, joined and I joined. I've only shot a couple of days so far, but I am heading straight back to do a couple of months of that. ... I'm pretty excited about it, actually."
So, what is it like introducing a new character after Cillian Murphy's gangster drama has already been up and running for three seasons?
"Cool. It's fine. It makes it easier, if anything. They've set it up. They've set the tone. They've done the hard work," Gillen said.
"Not that it slacks off. I've got to step up to the plate, too. It's such a vividly drawn world, so well established. It feels quite easy to just step into it. "
Gillen can now be seen on the big screen in "King Arthur: Legend of the Sword."
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