The Lone Defender

The Lone Defender is a 1930 American Pre-Code Mascot serial film starring Rin Tin Tin. It was Mascot's first all-sound serial (the second to have any sound at all, after the partial sound in The King of the Kongo). It was Rin Tin Tin's first serial at Mascot, after being dropped by Warner Bros. when they decided animal pictures would not work with "Talkies". He also starred in the later serial The Lightning Warrior, which was his last appearance (he died in 1932).[1]

The plot revolves around Rin Tin Tin as "Rinty" and a secret gold mine fought over by the criminal "The Cactus Kid" and the legitimate owners. Material from this serial was edited into a feature film version and released under the same name in 1934.

Prospector Juan Valdez is murdered by The Cactus Kid and his gang in an attempt to discover the location of his gold mine. Valdez's dog Rinty witnesses the murder and can also lead the gang to the mine, making him the villain's target throughout the serial. In addition Rinty must help Valdez's daughter Dolores legitimately find and claim the mine while being blamed for being the wolf that has been attacking local livestock.

The mysterious figure of Ramon is constantly on hand, overhearing pieces of the villain's conversations. He appears to be another bandit but his actions seem to contradict that. It is revealed in the finale of the serial that Ramon is in fact "Marco Roberto", an agent of the Justice Department.

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