The Marines Come Thru (1938)

Marine Lieutenant Steve Landers has perfected a new bombrelease for airplanes which he is testing with the aid of his mechanicsSingapore Stebbins and Jack Murray Dick Weber one of a group of enemy agents attempting to steal the plans is a friend of Colonel Dale whose daughter Linda is engaged to Landers Weber learns that Singapore and Jack are to deliver the final blueprints to the Colonels home Beckstrom head of the spy ring has some of his agents dress as Marines and obtain entry the the hangar They get the plans but Singapore and Jack have overheard a conversation that indicates the spies are heading for a nearby island which is the headquarters of the espionage group