Scientist Professor Goodman (Halliwell Hobbes) has found out a way to create perfect artificial diamonds and intends to give his invention away. Industrialist Sir Raymond Blantyree (Matthew Bolton) has made a lot of money from rocks and thus isn't too keen on diamonds suddenly being made worthless and so aims to stop the scientist...
To make matters more confusing a rival scientist Dr Botulian (Porter Hall) also wants to stop the competition and claim the artificial diamonds for himself. So begins capers across Europe back to London and various (and sometimes a bit confusing) disguises and cases of mistaken identity. Drummond is assisted by Algy (Reginald Denny) and Tenny (E.E. Clive) of course to various degrees...
Maybe not quite as fun as some other Bulldog Drummond films but a pleasing adventure romp complete with evil schemes, (mad) scientists with labs full of sparkling electricity and plenty of action including a final whip vs sword fight!
Light in tone the film has it's fair share of whimsy and nonsense including a penguin in a top hat. Long suffering police chief Colonel Nielson (John Barrymore) is on hand to continue squeezing life out the joke about his title.
