Of the 40,000 thoroughbreds foaled in the U.S. annually, only 20 make the regal two-minute run that is the Kentucky Derby, a Mardi Gras–like spectacle that brings out bourbon-drinking gawkers and gamblers, crazy hats and Carson Kressley, apparently. Galloping toward the 2006 edition of this holy-grail event, the Hennegan Brothers’ zesty directorial debut trails the prep season of six diligent horse trainers, including an optimistic MS patient who works for the prime minister of Dubai and a wheelchair-bound dad whose passions are undeterred by the irony that an equestrian accident caused his paralysis. Many of the subjects, we learn, are quite victorious year after year, but the Hennegans are deft enough editors to convince us of a six-way underdog competition, and the track sequences can be real nail-biters. Of course, if you’re not already a fan, the multitude of stakes races—which makes up the film’s bulk—eventually gets tedious, and one wishes for more detail on the personal dramas, off-track hooks in plain sight (why introduce one trainer’s 71-year-old father, who wants to be the oldest winning jockey, in the final minutes?), and sport’s controversies (maybe co-distributor Churchill Downs Inc. doesn’t know about PETA?). So First Saturday isn’t exactly a winner, but it places.