Who on earth would want to race on a motorbike at high speed down everyday roads with serious injury lurking at every corner? Commentator Murray Walker’s answer is those who ‘like to trace the knife-edge between safety and disaster’. No name is more closely associated with motorbike road racing than the Northern Irish Dunlop family. Joey Dunlop and younger brother Robert dominated the Isle of Man TT race and its Ulster counterpart the North West 200. This documentary traces the story of the Dunlops, who exemplified the obsessive dedication, perhaps even insanity, inherent in the sport. Shocking footage reveals the dangers they faced. But that hasn’t stopped Robert’s two sons following in his footsteps, which provides hair-raising rider’s-eye-view coverage. The tragedies and triumphs of the Dunlop dynasty will be well known to fans, so this retelling will have most impact on newcomers to their remarkable story.