Olympic icon Sir Chris Hoy heads to Japan, host of next year's Tokyo Games, to explore the Japanese phenomenon of the keirin, the most extreme and exciting event in track cycling. A test of controlled pacing then a tactical fight to the line, keirin is a sport in its own right in its country of origin, and is steeped in the history and rituals that make Japanese culture so unique. Attending keirin school is a once in a lifetime opportunity for international riders, and back in 2005, multiple Olympic gold medallist Sir Chris was one of the first Britons to be invited to savour the ultimate experience in the career of any track cyclist. He now makes a nostalgic return.