Columbia Pictures elevated stunt man Jock O'Mahoney to stardom in this 15 chapter western serial about the building of the transcontinental railroad. O'Mahoney played a railroad agent who uncovers the master criminal behind a series of sabotage attempts on the construction site.

A woman reporter, a navy investigator, and a heavyset police detective come across a gang which scuttled a ship in order to loot her later, underwater, for a Navy money consignment.

Shemp's rich Uncle Phineas comes to visit the stooges who are broke and about to evicted. The boys convince their landlady Mrs. McGruder not to toss them out as Shemp is set to inherit a fortune. The boys also have trouble with a circus strongman after Shemp accidentally rips off his wife's dress. Uncle Phineas gets in the middle of the fight, and Mrs. McGruder ends it by knocking out the strongman. It turns out that Uncle Phineas and the landlady were childhood sweethearts and he marries her, leaving the stooges out of the bucks once again.

The entertainment duo Mitchell & Petrillo, en route to a USO show for troops in Guam, fall out of their plane and end up on the jungle island of Cola Cola, where the mad scientist Dr. Zabor is conducting evolutionary experiments.