The film hinges on the love triangle between a young aristocratic lady on the run (Cleonie, played by Hazel Terry), the murderous Varennes, Citizen-Deputy of the Revolution who saves her by disguising her as his nephew (Nils Asther) and finally the Marquis of Corbal of the film's title, played by Hugh Sinclair.
Joyce Reid, a wealthy young debutante, stows away on a cargo ship to China, carrying as passengers her dashing aviator sweetheart, Dan Bailey and and her munitions-producing father, E.
Peyton Wells (Ben Lyon) rescues Judy Jones (Joan Marsh) from a very dull young man, at a sedate party given for her by her multi-millionaire grandfather Silas P.
A retired Scotland Yard detective, Patrick Fitzpatrick (Tom Walls) comes back to take one final case, tracking down a missing vase which has been stolen by a gang of thieves specialising in taking art treasures.
Hoping to rid a small western community of its corrupt political machine, Ken Marshall (Ken Maynard) runs for sheriff against the bad guys' candidate and wins the election.