Hopalong Cassidy and Johnny Nelson ride to the mountains to help a man and his daughter save their logging business from someone who is sabotaging their efforts.
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, Johnny and California go to Arabia to buy some horses. There they get involved with a sheik and a harem and a kidnapping plot.
