How do leaders become legends, and how does a writer expose the person behind the public face? David Marr has explored the lives of controversial politicians, eminent journalists and literary luminaries. Julia Baird revisited the life of a monarch for Victoria: The Queen, Wilson imagined the life of naturalist George Forster, who travelled with Captain Cook, and Troy Bramston wrote a sweeping biography of Paul Keating. David Marr leads a spirited discussion about why there is no such thing as a definitive biography.