The outbreak of World War I places Scots officer Geoffrey Richter-Douglas in an uncomfortable position. Although his allegiance is to Britain, his mother was from an aristocratic Bavarian family, and he spent his summers in Germany as a child. When Geoffrey is approached by a German spy who offers him a chance to defect, he reports the...

Romanian-French gigolo Georges Iscovescu wishes to enter the USA. Stopped in Mexico by the quota system, he decides to marry an American, then desert her and join his old partner Anita, who's done likewise. But after sweeping teacher Emmy Brown off her feet, he finds her so sweet that love and jealousy endanger his plans.

Buck Peters arranges for Hoppy, California, Johnny and other cowboys to go to the aid of friends whose cattle are being rustled. Hoppy and California locate the rustlers' hideout and join the gang by posing as outlaws themselves, but must find a way to let the rest of the posse know where they are.

Hoppy, California and Johnny come to the ranch of a friend and his daughter, disguised as dude detectives from the east, to investigate the disappearances, without a trace, of several herds of cattle.

Escaped criminal "The Fox" hates Hoppy and a Rurales colonel for imprisoning him and lures Cassidy to Mexico in order to exact his vengeance.