Joe Bascom was implicated in an oil stock swindle in Iowa. He is pursued by authorities even though he was a victim, more than a perpetrator. He heads to Mexico where he believes Harry Lambert, the real con man, has gone. Once there, he finds Harry has helped a mutual acquaintance, Mary, become a toreador known as Montana. Harry, Dagmar (another woman) and Mary are in cahoots with Gus Adamson to launch a new silver mine scam in Mexico. The key to it is having Montana toss her hat to Gus in a promotion to select the Amigo Americana Week honoree. With all the planned appearances, it will make a perfect platform to pitch the phony stock. Mary sees Joe in the crowd and tosses the hat at him in a fit of anger. Suddenly, Joe is a celebrity. He changes his name to Humphrey Fish to stay away from two US policeman who are pursuing him. Harry manages to recruit Joe into their scheme, but they don't count on his basic honesty. He keeps the money from the new stock sales to return to the investors. Dagmar tries to trick him into revealing where he hid the money but falls for him in the process. She takes it, but returns it to him in a bull ring, complete with a bull.