S18, E6: On Graham's sofa tonight: making her first British chat-show appearance in 42 years, Dame Maggie Smith, starring in the new film `The Lady in the Van' with Alex Jennings who joins her on the sofa, four-time Oscar-nominated Bradley Cooper and British star Sienna Miller, co-starring in a new chef movie `Burnt' and chat and music from Justin Bieber, who performs the chart-topping single `What Do You Mean?'