How did carols come to tell of Christ? In today's programme Sir Geraint shows how the church in the Middle Ages began to sell the Christmas story to the people at large, by taking over popular forms of entertainment that already existed. The result was that from Medieval mystery plays to modern nativity plays, drama, dance and carols came together to express the joy of Christmas. Today's carols: 'Ding dong! Merrily on high', 'The Coventry carol', 'The cherry tree carol', 'Shepherds have left their sheep', 'Personent hodie'.