A former surgeon, Keenan lost his arm yers ago when he saved Mrs. Forchune from a saber-wielding native in South America. The Forchune’s put Plain into their will for his bravery. Keenan attached a blowtorch to his arm instead of a normal artificial arm and then killed the Forchunes for his willed inheritance. Tracy uncovered his scheme and tracked him down. Plain resisted arrest, using his blowtorch and Tracy shot back, striking him several times. With limited visibility because of the smoke, Keenan ran into the street and a gasoline truck overturned and spilled fuel over him. Mr. Plain died horribly.