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Used earlier in The Phantom Empire (1935), S.O.S. Coast Guard's weird disintegrating effects, highlighted in both the opener and chapter three, were created by blowing up key scenes onto soft gelatin-like photographs, then heating the images. The effect remains startling even today and this kind of inventiveness quickly made Republic the serial maker to beat, at least when it came to creating the right atmosphere for the goings-on. Other studios such as Universal may have had the upper hand when it came to story and character motivation, but the little upstart company in the San Fernando Valley employed the best behind-the-scenes craftsmen in the business.