In the rarefied world of the Cresta Run, that headlong, terrifying, exhilarating icy descent through St Moritz on little more than a tea tray, Billy Fiske has long been a hero, revered as a magical figure who was not only the fastest runner of his generation but also the one who never crashed. His death during the Battle of Britain, one of the first American pilots to die in the Second World War, only burnished his halo for those who knew or knew of him. It is his story that is at the heart of Andy Bull’s Speed Kings, an enthralling account of the four men who won gold for America in the bobsleigh at the third Winter Olympics in Lake Placid in 1932.

Billy Fiske, whose father was a senior partner at the US bank Dillon, Read & Co, was brought up in luxury, first in Chicago and then in Paris. At thirteen he was sent to school in England, a