After completing a PhD in particle physics, Simon joined the BBC, working on series such as Tomorrow's World and Horizon. After directing a documentary about Fermat's Last Theorem, which won a BAFTA, he turned to writing and has since authored books on maths, codes and cosmology. After being sued for libel (and successfully defending his writing) in 2008, Simon was at the forefront of the Libel Reform Campaign, which resulted in the 2013 Defamation Act. He is currently working on a project aimed at supporting mathematics in schools.