Sgt. Renfrew and Constable Kelly go aloft to search for a plane missing with a shipment of gold from the Yukon Mine Company. Inventor Speavy has devised a power ray which disrupts electrical impulses, and Morgan and his gang of crooks has brought in Prof. Lewis to increase the ray's range, telling him he's helping the government develop this new weapon. Speavy spills the beans to Prof. Lewis and his daughter Madeleine,and Morgan threatens to implicate them in his crimes unless they cooperate. Morgan kills Speavy when he tries to warn Renfrew, but when Madeleine stows away on board the doomed plane Renfrew is piloting, will the crooks be able to make Prof. Lewis use the power ray to bring the plane down?

Sky Bandits (1940)

The British sleuth's fiancee helps him chase spies who killed an inventor and stole his death ray.

Arrest Bulldog Drummond (1938)

A professor has an invention that will bring down planes, causing them to crash, and Dawson is forcing him to use it on those carrying money. When Tim arrives to investigate, he is mistaken for a noted outlaw. So he assumes that identity to force Dawson to make him a partner. But just as the plane bringing Tim help is arriving, his true identity is revealed, and while he is a prisoner, Dawson forces the Professor to start his machine.

Death Rays!