This documentary tells their stories: 14-year-old Rachel who gave her two-year-old sister life-saving mouth-to-mouth resuscitation; Don, who delivered his own child (with wife Jeanette, of course); and Graham, who punched the chest of a man who who had stopped breathing - a "precordial thump", as seen on Casualty. It's all very heart-warming stuff, which shows that TV can really be a force for good.