Secret Service Major Steel is one of the few men in America aware of the fact that Captain Albright is also Captain Midnight, daring masked aviator dedicated to fighting gangsters and enemies of America.

The three Morgan brothers, Glenn, Jim and Buddy are all air mail pilots. The plane flown by Jim is shot down by Hugh Jeffries for the money it carries. Another flight is made by Buddy followed by Jeffries intending to shoot him down also...

The wife of a businessman and his secretary attempt to trick her husband's double into impersonating him so they can get their hands on what remains of his wealth.

A group of passengers are trapped in a runaway Pullman car.

A judge who had taken part in the gold rush of 1849 hires an acting troupe to recreate the experience in this rather fanciful silent Western. The make-believe turns serious when a real gold mine is discovered nearby and a local girl is kidnapped by a nasty gambler.

Diamond thieves have infiltrated the staff of O'Day Jewelry. The Los Angeles Police Dept. employs their newest weapon, an airplane, to help smash the diamond theft ring.