As a junior he wound up in the same fraternity as a guy named Bob Baffert, who was already riding winners, already conspicuous. Eric Kruljac, for his part, had transferred to University of Arizona from Arizona State, where he had been on a football scholarship only to blow a knee. Then, when Baffert proceeded to stardom at the racetrack, Kruljac literally went undercover. He worked for a buddy as a private investigator until, having learned the ropes, starting an agency of his own. For several years you'd find him tailing...