At 93, Antonia Fraser, one of our leading historians, has written her 40th book – The House that Spoke: The History of a Home.

She tells Harry Mount about 70 years of writing, going all the way back to her 1954 debut, King Arthur and the Knights of the Round Table. And she talks about her west London house, where she wrote her 1969 bestseller, Mary, Queen of Scots – and her late husband, Harold Pinter, wrote Betrayal in 1978.