"Tailspin Tommy" Tompkins and "Skeeter" Milligan are training young U. S. Army fliers for the newly-formed 'Sky Patrol,'a branch of the Army Reserves which operates along the borders and coast-lines, on the lookout for smugglers. Carter Meade, whose father is the Colonel in charge of the patrol, has a terror of firing guns and his father insists he conquer this fear. Tommy sends him out on patrol, on orders from Washington D. C., to stop any unfamiliar aircraft. Carter challenges an unmarked amphibian plane, which opens fire on him. Carter, afraid to shoot, bails out as his plane is shot down. Carter is missing, and Tommy and Skeeter are searching for him and the mysterious airplane.