Game of Thrones star Gwendoline Christie has revealed the new season of the hit show will “push the boundaries of the way we view television”.

The Worthing-born actress plays woman warrior Brienne of Tarth in the HBO hit series based on the novels by George R R Martin. She told online magazine Access Hollywood: “Every year I think, ‘How can they possibly top it? How can they make this better?’ Every year I get a moment of ‘I can't believe they did that!’ But this year, they’re doing things that are so unconventional that I think it’s really pushing the boundaries of the way we view television.”

Season five of the fantasy series featuring the warring families the Lannisters and the Targaryens is set to hit the screens on Sky Atlantic in April, and next month the world premiere, showcasing the opening episode, is to be held in London for the first time. The red carpet will be rolled out at the Tower of London on March 18, with fans hoping statuesque Gwendoline, who is 6ft 3in, will be among the show’s stars attending the prestigious event. “I can’t think of a more fitting venue to give what promises to be another unmissable series its big launch,” Sky Atlantic’s director Zai Bennett said.

The show’s producers are keeping tight-lipped about what viewers can expect in series five, but Martin has announced that it features unexpected deaths. “People are going to die who don’t die in the books,” the author told the Writers Guild West Awards recently. “Everybody better be on their toes.” He said that writers David Benioff and D.B. Weiss “are even bloodier than I am”.

Gwendoline, who will also appear in the movies The Hunger Games Mockingjay: Part 2 and Star Wars Episode VII, both released later this year, is one of the series’ best-loved characters and her determination to win the role is already a legend. According to Martin, she prepared for her audition by cutting her long hair short, wearing unisex clothes and gaining a stone in muscle after undergoing an intensive training regime. She arrived dressed and made up as Brienne, and after landing the role learnt horsemanship, sword-fighting and stage fighting. “I don’t think I’ve ever wanted anything as much,” she said later.

Worthing actor Brenock O’Connor, 14, will also appear in nine episodes of season five, reprising his season four role as Olly, a boy from the Gift.