"The Edge" by Dick Francis [UNABRIDGED AUDIOBOOK WITH TEXT]
All aboard for the Great Transcontinental Mystery Race! This glittering event will take international racing VIPs and their thoroughbreds to races across Canada aboard a luxury train. Along the way, an intriguing mystery enactment will provide entertainment. Tom Kelsey is the security agent assigned to keep tabs on one of the most vicious figures of the racing underworld. For years he has been after Julius Apollo Filmer, a slippery criminal who "persuades" owners to sell their prize horses. Now Filmer has bribed his way onto the Mystery race, and the murder mystery threatens to become all too real.