Best known for Dad's Army, in which his Sergeant Wilson played the languid, rakish foil to Arthur Lowe's pompous, chippy Captain Mainwaring, John Le Mesurier was one of Britain's favourite and most recognisable character actors. The epitome of insouciance and languor on screen, in real life this charming, quietly-spoken bon viveur was plagued by private turmoil and heartbreak. Married three times, he saw his first wife succumb to alcoholism, his second - the comedy diva Hattie Jacques - move her lover into the family home, and his third enjoy a passionate dalliance with troubled comic Tony Hancock. As Graham McCann reveals in this fully authorised and moving biography, as an actor John Le Mesurier was a key ingredient in the success of Britain's greatest sitcom, but as a man he was far more courageous than Sergeant Wilson was ever meant to be.