In 1940, Canutt sustained serious internal injuries when a horse fell on him while doubling for Clark Gable in "Boom Town" (1940). Though in discomfort for months after an operation to repair his bifurcated intestines, he continued to work. Republic's Sol Siegel offered him the chance to direct the action sequences of "Dark Command", starring Wayne and directed by Raoul Walsh. For "Dark Command", Canutt fashioned an elaborate cable system to yank back the plummeting coach before it fell on the stuntman and horses; he also created a breakaway harness from which they were released before hitting the water.