In the 1920s and 30s, there were quite a few Bulldog Drummond films but the series suffered because they never seemed to keep a leading man for long and the style of the various films varied so much. The strangest of these is "The Return of Bulldog Drummond", as Drummond and his friends are less super-heroes and more super-vigilantes...and violent ones at that.
The context for this film is VERY important and might get lost on some viewers. So, I'll try to explain. In the 1930s, Europeans and Americans (apart from those in Nazi Germany) were sick of war. WWI had left many millions dead and the people thought that perhaps this god-awful war would be their last because it was so terrible and destructive. As a result, many anti-war films came out during this era, such as "All Quiet on the Western Front" and "J'Accuse" were popular and reflected these sentiments. And, in many ways, this Drummond film fits in with this pattern.
When the story begins, some sickos have been murdering various folks campaigning for disarmament and peace. You can only assume that these unknown people are working for the armaments industries...the same profiteers who benefited from the carnage of WWI.
Bulldog Drummond (Ralph Richardson) and his gang of vigilantes (referred to as either 'the Black Gang' or 'the Black Clan' in the film) want to stop these murderers and profiteers....and you assume much of it is because they are all WWI veterans. They are willing to do just about anything to stop these schmucks...even kill them if necessary!
The story is more taut and violent that other Drummond films. This also makes it one of the better Bulldog Drummond flicks...which is a shame, since this more British version is the only one Ralph Richardson made. Well made and well worth seeing.