Lesser is a frequent radio contributor and played the title role in the BBC Radio adaptations of the first five Falco mysteries by Lindsey Davis. He has also recorded many audiobooks, including much of the work of Charles Dickens, and his recording of Great Expectations won him a Talkie Award. Other books range from John Milton's Paradise Lost and Homer to contemporary novels by Robert Harris (Fatherland) and Philip Pullman. For two months in 2013, Lesser was heard as a regular cast member playing Robin Carrow in Ambridge Extra, a BBC Radio 4 Extra spin-off from the BBC Radio 4 drama The Archers.