John Casey (George O'Hara) is a Coast Guard officer stationed on Long Island Sound. He is both hated and feared by a band of smugglers headed by Diamond Kate. The serial unfolds with the smuggler gang choosing their strike against Casey on the night of the Cadet Coast Guard Ball. Casey’s brother Frank answers the call that night and is killed in action against the smugglers. Casey vows to avenge the death of his brother.
Fur trapper Brule Conway sets Rin Tin Tin Jr. to guard his furs. The henchmen of a rival trapper use a female dog to lure Rinty away from his post, and then proceed to steal the stash of furs. Rinty sets out to capture the thieves and return his master's furs.
Rom Ritthikrai (Mitr Chaibancha) is at a nightclub getting very drunk and trying to persuade others to join him in his fun. He is retrieved by his faithful assistant Oy (Petchara Chaowarat). Rom is actually the masked crimefighter, Insee Daeng, or Red Eagle, and he uses the persona as a fun-loving drunkard as a cover.