A fifth series from BBC Radio 4 in which Stephen Fry examines, with the help of experts, the highways and byways of the English language. In these four episodes he tells The Story of X: a letter holy and profane, sexy and chaste; discusses intonation, the "song" of English and how cadence affects meaning; muses on the art and craft of conversation - and whether true conversation can happen on TV and radio - and ponders the meaning of meaning, and the gap between brain and mouth that means language can never truly represent thought. In addition, he tells us why blue as a colour is a newish invention.