Best selling author Jodi Picoult on her latest book and Brendan O'Carroll discusses his hit creation, TV show, Mrs Brown's Boys. Mark Lawson takes a tour of the newly opened 'The Harry Potter Experience' and talks to conductor Sir John Eliot Gardiner. John Wilson meets singer and songwriter Dr John and talks to the Polish composer Krzysztof Penderecki about his work with Radiohead's Jonny Greenwood