Heroes of the Flames

Heroes of the Flames is a 1931 American Universal movie serial. Although once considered to be lost, it has survived and a print has been preserved by Universal as of 2016. It stars Tim McCoy as a firefighter who is developing a new kind of flame retardant, but his work is constantly being disrupted by a rival named Don Mitchell who wants the formula for himself as well as the leading lady, played by Marion Shockley. Fittingly, seven of the 11 cliffhangers involve burning buildings with at least one principal trapped inside.

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