Shortly before Pearl Harbor, American opportunist Jones and partner Johnny are in China to sell oil to the invading Japanese army. Cynical about the sufferings of the Chinese, Jones meets compassionate teacher Carolyn Grant while travelling cross-country to Shanghai. Sparks fly between these strong-willed characters, neither budging an inch. But when Jones witnesses a Japanese atrocity, his feelings toward his customers (and Carolyn) begin to change...

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.

In the 1840s, Ramsey MacKay, the driver for the struggling Wells Fargo mail and freight company, will secure an important contract if he delivers fresh oysters to Buffalo from New York City. When he rescues Justine Pryor and her mother, who are stranded in a broken wagon on his route, he doesn't let them slow him down and gives the ladies an exhilirating ride into Buffalo. He arrives in time to obtain the contract and is then sent by company president Henry Wells to St. Louis to establish a branch office.

Ace owns just about everything around except for the Bank, which is owned by John Ware. Ace also has his eye on Judy, but Judy only has eyes for Clay. Since Ace is a crook, he holds up the stage and has his cronies swear that Clay was the bandit which gets Clay 10 years in jail. After he gets out in 5 for good behavior, Clay sets out to find who framed him and stole the stage strongbox. Since the sheriff does not like Clay, he takes his guns away as part of his probation and it makes Clay a target for the Ace gang.

Americans Tommy Baldwin and Joe Dugan are hired to transport a fabulous diamond from Shanghai to San Francisco. They will be paid handsomely on success or killed on failure. The diamond is stolen as they take possession of it.