Watch Sadisflix. As an athlete with an impairment drives his 7-year-old daughter and 5-year-old son to run one of their first triathlon races, he recalls the most difficult challenge he ever faced: an Ironman; one of the most strenuous physical and mental races involving 3.8 km of swimming, 180 km of biking and a run of 42 km, in a single day. The movie explores how children perceive this crazy idea.