She has worked with Robert Redford, been nominated for Oscars, and won Best Actress prize at Cannes, but Vera star Brenda Blethyn admits that she still has imposter syndrome. “I think a lot of people have got it,” the legendary actress says in an exclusive chat before she guest stars at the Theakston Old Peculier Crime Writing Festival in Harrogate tomorrow (12pm, Sunday, July 26).