Personal Identity is at the heart of contemporary culture. Political philosophies are built around it and family history is a hobby undertaken by hundreds of thousands. Understanding where you came from is seen as central to understanding who you are. But what if the things that are uncovered are uncomfortable, upsetting or even life-changing?

Matthew Sweet is joined at the Hay Festival by three writers who have hosted podcasts which raise these questions – Joe Dunthorne, whose memoir Children of Radium and BBC Radio 4 series Half Life explore his great-grandfather's work with chemical weapons; Kavita Puri, whose series Three Million told the story of the Bengal Famine, and of British culpability in it; and Jenny Kleeman, whose BBC Radio 4 podcast The Gift tells the stories of lives upended by DNA testing kits. How does the format of the podcast help them explore these complicated subjects?

The Gift, Three Million and The History Podcast, Half Life are all available now on BBC Sounds

Producer: Luke Mulhall