Journalist, controversialist, celebrity - Mark Coles explores the explosive career of Piers Morgan, one of the country's youngest-ever and best-known newspaper editors. In the spotlight, again, this time for storming off the set of ITV's "Good Morning Britain", colleagues, competitors, friends and foes detail a roller-coaster career. If it started with a desire to report from behind the headlines, as years passed he has all too frequently become their subject.