Professor David Cesarani exposes one of Britain's greatest blunders of the Second World War- the mass internment of 27,000 civilians, many of them innocent refugees from Nazi Germany. He hears of the months wasted languishing behind barbed wire and how hundreds of internees died when the boat taking them to Canada was torpedoed. There were brighter stories too, such as the formation of the Amadeus String Quartet during internment. Producer Hugh Levinson