Frankel: the full story of the world's greatest racehorse

As Frankel faces his final race, Brian Viner talks to his trainer, Sir Henry Cecil, and others who know the world's greatest racehorse best.

FRANKEL. It is not a name that rolls off the tongue, like those of some other great thoroughbred racehorses, such as Nijinsky, Mill Reef and Brigadier Gerard.

But in racing people it ignites sheer wonder, for Frankel is the superstar of Flat racing, not simply unbeaten in 13 races, but untouchable.