For George Gregory—one of nine participants in the Fort Worth, Texas, horse-training competition profiled in this doc—the process of taming one of the 100 wild mustangs the government rounds up from public lands every year is “as good as it gets.” The horse was unavailable for comment. That about sums up the good and the bad of this documentary from husband-and-wife directors Alex Dawson and Greg Gricus: Even its most interesting human subjects can’t compare to the beauty and enigma of the wild horses who, after a life of running free, find themselves forced to two-step and bow to bizarre commands. We duck among contestants—including the aging Gregory and his wife, a showboat blonde, and two Native American ranchers—as they prepare over three months for the “Extreme Mustang-Makeover Challenge.” The horses are fresh off the plains, and the strangely tender, almost romantic dance of first contact is beautifully captured. We get some sense of the horses’ range of personalities; clearer is the nature of each trainer’s attachment. The actual competition proves anticlimactic, as the focus pivots away from these mysterious creatures, who suffer us and all our schemes and presumptions with what can only be called grace.