"Oh I think he would be a brilliant Bond," says Dench. She will not actually be there to order Elba around as M — her character died in 2012's Skyfall — but will star with him in a film adaptation of Andrew Lloyd Webber's Cats, playing Old Deuteronomy to Elba's Macavity.
Ask her what she thinks of the other prime Bond contender, Richard Madden, and she is bemused: "I don't know Richard Madden." He was in Bodyguard. "Oh." Still nothing. (She doesn't watch much television, she says, apart from University Challenge, which she "dotes" on).
When Dench discovered she was to die in 007's arms in Skyfall — having played M in seven Bond films — she burst into tears. Audiences felt similarly bereft. But in the forthcoming Trevor Nunn wartime spy drama, Red Joan, she proves she's just as good a spy as spymaster. Inspired by the true story of a KGB source called Melita Norwood (Joan Stanley) — who helped speed up Stalin's atom-bomb programme by passing British nuclear secrets to the Soviets — Red Joan is about the coming of age of a woman in the 1940s, the ethics and moralities of patriotism and treason, and the dangers of underestimating women.
Underestimated first as a Cambridge atomic physics undergraduate and then as a pensioner charged with treason 40 years on, Joan "either comes out of it as a heroine or not — depending on what you believe yourself", says Dench.
"I certainly don't think [Joan] thought of herself as a heroine. She said she believed in everyone having the same nuclear information, so that it would be less likely that people would attack one another and go to war."
Despite a glittering acting career, she's not complacent. "Because you can go off the radar, you see ... And I do not want to go off the radar.
"If I'm offered a job I always do it, because I think it's the last job I'm going to be asked to do."
Does she feel everything is more agenda-driven today in the industry? "I do think it's very difficult for young actors of a certain age to get cast now," she says slowly.
"I absolutely admire the 'all women of colour' idea," she goes on, referencing productions such as the Richard II currently showing at Shakespeare's Globe, which has women of colour in every role, "but if it's all going to swing one way then it's leaving a whole lot of other people out as well. Attitudes have changed so much in the last 10 years that you don't quite know where you are any more."
Is it mostly for the better, though? "In some cases, but not all," she sighs. "More parts for women, yes — that's terrific — but other young actors who might want to do Shakespeare are being done out of parts because they're being played by women. So it's a kind of dichotomy."
• Red Joan is in New Zealand cinemas from April 8.
