Hannah Fry is an Associate Professor in the mathematics of cities from University College London. She is also the author of The Mathematics of Love, The Indisputable Existence of Santa Claus and Hello World and regularly writes for The New Yorker. In her day job she uses mathematical models to study patterns in human behaviour, and has worked with governments, police forces, health analysts and supermarkets. Her TED talks have amassed millions of views and she has fronted television documentaries for the BBC and PBS. With Adam she co-hosts the long-running science podcast, 'The Curious Cases of Rutherford & Fry' with the BBC.