There are two new players on the Game of Thrones board in season three portrayed by a pair of respected actors: Wildling leader Mance Rayder (Ciarán Hinds) and Tyrell matriarch Lady Olenna (Diana Rigg).

When it came to finding Rayder, Thrones producers sought a strong, rugged and charismatic actor. Rayder, a former member of the Night’s Watch, has managed to unite all the disparate tribes of the North. Yet author George R.R. Martin’s saga also subverts readers’ expectations by depicting Rayder as a rather unremarkable-looking man who can pass for an unassuming and wily musician.

“Of all the various kings vying for power, in some ways Mance has the greatest challenge,” showrunner David Benioff says. “He wasn’t born to be a king. He wasn’t even born a lord. It’s not a hereditary title, and he’s not ruling over one homogenous group of people. He’s brought together these various tribes who speak different languages. What he’s done is, in my mind, more impressive than what any of the other pretender-kings have done. In order to capture that on screen you need somebody who has that charisma.”

When producers announced the 60-year-old Hinds for the Rayder role last year, fans were divided: Some thought the casting was fantastic — Hinds was compelling as Julius Caesar in HBO’s Rome. Others say they pictured Rayder differently — younger, mainly (a common initial reaction to the casting of many parts on Thrones, which, often by necessity, has aged-up several characters).

“Ciarán has such an inherently regal presence on screen,” says showrunner Dan Weiss. “It takes a certain kind of person with a certain gravitas and charisma to convince all those people to lay down their arms and put their differences aside and follow him … for us, that’s what Ciarán brought. He just commands respect from others — they way people felt around him as a person — and that carries over into the performance.”

This season Jon Snow (Kit Harington) must convince Rayder he’s truly defected to the Wildlings while he gathers information about their impending invasion of Westeros. Harington said he was “overwhelmed” when he learned of Hinds’ casting.

“He’s one of our national treasures, one of our great British actors,” Harington says. “He’s incredibly magnetic. He’s perfect for Mance. He’s got these crazy intense eyes. It’s another paternal figure for Jon to look up to, in a strange sort of way. He wants to hate Mance, but ends up liking him.”

Over in Thrones‘ warmer climate of King’s Landing, we’ll meet another regal figure in season 3: Lady Olenna, the grandmother of Joffrey’s (Jack Gleeson) latest bride-to-be Margaery Tyrell (Natalie Dormer). Olenna, also called The Queen of Thorns, is sharp-tongued and quick witted. Expect her to take an interest in Sansa Stark (Sophie Turner) and her granddaughter’s impending marriage.

For the role, producers chose 74-year-old Rigg, who starred in the original 1965 TV series The Avengers and whose Bond girl character married 007 in the film On Her Majesty’s Secret Service. It was one of those castings that everybody agreed was spot-on (plus, she’s Dame Diana Rigg, so now Thrones has nobility playing royalty).

The producers recall having their first meeting with Rigg after she had caught up watching the show. Weiss says the actress gave the producers a big charming smile and said, “There’s an awful lot of bonking, isn’t there?” Rigg then arrived for her first table read and blew away the team by having already memorized her entire role for the season. “It was inspirational for the other actors,” Weiss says. “We knew she was the perfect Lady Olenna.”

Fans of Martin’s novel can also expect some great scenes with Olenna that were added from the books, with the Queen of Thorns matching wits with Tywin Lannister (Charles Dance) and Varys (Conleth Hill).

Oh, and for the record, Martin approves the castings, too. “They’re both sensational actors,” the author said. “I’ve been in love with Diana Rigg since The Avengers. She’s done amazing work since and she’s going to be an amazing addition to the show. I knew Ciarán primarily from Rome and he was sensational as Caesar. He’s slightly different than Mance as described in the books but we’ve been through that before.”

DAY 11 UPDATE!: So we’re two-thirds of the way through EW’s 15 Days of Thrones. Only one week left. And I’m thinking: Why do only five more days of daily Thrones posts? There are seven more days until the show’s premiere and Westeros has seven kingdoms. Coincidence? No way! Let’s spur this stallion and keep mounting these posts every day until the premiere, weekend be damned. We’ve saved some biggies for the home stretch — there are exclusive interviews coming up with Peter Dinklage, Lena Headey, Emilia Clarke and a fun one with the showrunners.

17 DAYS OF THRONES

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