Melvyn Bragg and guests discuss the work and ideas of Dorothy Crowfoot Hodgkin (1910-1994), awarded the Nobel Prize in Chemistry in 1964 for revealing the structures of vitamin B12 and penicillin and who later determined the structure of insulin. She was one of the pioneers of X-ray crystallography and described by a colleague as 'a crystallographers' crystallographer'. She remains the only British woman to have won a Nobel in science, yet rejected the idea that she was a role model for other women, or that her career was held back because she was a woman. She was also the first woman since Florence Nightingale to receive the Order of Merit, and was given the Lenin Peace Prize in recognition of her efforts to bring together scientists from the East and West in pursuit of nuclear disarmament. With Georgina Ferry Science writer and biographer of Dorothy Hodgkin Judith Howard Professor of Chemistry at Durham University and Patricia Fara Fellow of Clare College, Cambridge Producer: Simon Tillotson