Arrest Bulldog Drummond

Bulldog (John Howard (American actor)) and Algy (Reginald Denny (actor)), in the midst of preparations for the former's wedding in London, are summoned to more important matters at the house of an eccentric scientist who has invented a prototype electric "death-ray" device which has the potential to revolutionize warfare. They find the scientist murdered in mysterious circumstances upon their arrival, and set out to find out what is going on and the culprit, aka ''The Stinger'' - leading to trouble with Scotland Yard, a dock-yard knife-fight which puts the Bulldog on the missing-in-action list temporarily, and a trip to the tropics to foil a master criminal's attempt to sell the secret weapon to a foreign power for the highest price. Phyllis Clavering (Heather Angel (actress)), Drummond's fiancée, goes on a cruise with her aunt Meg (Zeffie Tilbury) to the tropics, where she brings Drummond to the crooks, Lady Beryl Ledyard (Jean Fenwick) and Rolf Alferson (George Zucco).