Forty years ago, the large blue butterfly was extinct in Britain. The intensification of farming has pushed half of the butterfly species in the UK to the brink of extinction. However, at Daneway Banks Nature Reserve in Gloucestershire, the large blue butterfly has made a comeback.

In this episode, Biology masters student Tosca Hulett discusses the extinction an re-establishment of the large blue butterfly with Professor Jeremy Thomas, one of Europe's most accomplished butterfly experts.