When the hammer thwacked down at Christie’s New York in November 2017, the ‘Salvator Mundi’ attributed to Leonardo da Vinci went for $450 million, making it the world’s most expensive artwork ever sold. But who bought it, who actually painted it and where is it now? 

Guest: Ben Lewis, art historian and documentary-maker

Ben's book is 'The Last Leonardo: The Secret Lives of the World's Most Expensive Painting' (Penguin Random House)