Game of Thrones: Dame Diana on playing Lady Olenna Tyrell

Actress Dame Diana Rigg has told BBC HARDtalk's Stephen Sackur about playing the role of Lady Olenna Tyrell in television drama Game of Thrones and the importance of making roles believable.

"I wasn't aware I was getting involved in something so huge. I really had no idea," she said, adding that her character is "pretty evil, I'm good at evil."

After a career spanning five decades, including her role as Mrs Peel in The Avengers, Dame Diana says the secret to great acting is "to measure the distance between yourself and that part and you have to fill it, fill it with truth", bringing to bear experience and understanding of the human condition.

You can see the interview in full at these times on BBC World News and the BBC News Channel and on BBC iPlayer (UK only).