The British Secret Service is on Captain Gringo’s back, seeking information on a Scottish pearl-trading colony on the Caribbean coast. Gringo’s in the dark as well – until a voluptuous redhead lures him into her bedroom to show him her collection of exotic pearls. From there it becomes a real knock-around time for the big Yankee soldier of fortune, fending off Carib gals and Scottish lassies, fighting a land-grabbing Spanish grandee and his death-dealing dirigible – and battling British imperialists who want to bring the pearl-rich colony to its knees!