Mornington Crescent is a game whose rules and history are shrouded in myth and mystery. Now, in this extended version of a spoof documentary first aired on BBC Radio 4, the team from "I'm Sorry I Haven't a Clue" research shine a light in the dark. As if that wasn't enough, Humphrey Lyttelton, Graeme Garden, Tim Brooke-Taylor and Barry Cryer also provide readings from two learned books on the subject: "The Little Book of Mornington Crescent" and "Stovold's Mornington Crescent Almanac". From Roman times to Chaucer and beyond, "Mornington Crescent" has become a legend in its own tube stop. Now, at last, its true history can be told.