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Directed by B. Reeves Eason and former editor Joseph Kane,
this Flash Gordon imitation was the second serial from a then
newcomer in the field, Republic Pictures. Actually, it was only the
Republic Eagle trademark that was new; Undersea Kingdom was
produced by Nat Levine, formerly of Mascot Pictures, a serial
kingdom all its own which had been incorporated into Republic in
1935, lock, stock, and Gene Autry. Not to be outdone by Universal's
blond superhero, Undersea Kingdom had Ray Crash Corrigan,
crash-helmet and all, diving into the ocean in a fantastic super
submarine. Corrigan and his passengers -- Professor Norton (C.
Montague Shaw), the professor's young son (Lee van Atta), brash
newspaperwoman Diana Compton (Lois Wilde), and a couple of sailors
-- are headed toward the legendary sunken continent of Atlantis.
Upon arrival, the surface people discover that the recent rash of
undersea earthquakes are the work of Unga Khan (Monte Blue), the
leader of the evil Black Robes whose nefarious goal is to destroy
America. Unga Khan's kingdom proves to be a mixture of
science-fiction gadgetry and medieval derring-do, both the Black
Robes and their enemy, the White Robes, dressed like something out
of a Wagnerian nightmare. The surface people ally themselves with
the White Robes and in the 12th and final chapter, Ascent to the
Upperworld, Corrigan et al. finally manage to rid both worlds of
the evil Khan. Republic threw everything but the kitchen sink at
the Saturday matinee crowd this time around, including such veteran
action and Western players as William Farnum, Raymond Hatton,
Smiley Burnette, Lon Chaney Jr., Lane Chandler, Malcolm McGregor,
and John Merton. Undersea Kingdom also employed most of the stunt
men whose work would eventually help make Republic the pride of
Poverty Row: Eddie Parker, Al Seymour, George de Normand, Tom
Steele, and the Yrigoyen brothers, Bill and Joe. Undersea Kingdom
was also released in an edited feature version, retitled Sharrad of
Atlantis. ~ Hans J. Wollstein, All Movie Guide