Another in the long-running Bulldog Drummond series, more exciting spy adventures in a Britain which always seems covered in fog.
Drummond (John Howard) is ready to head to Switzerland with Algy (Reginald Denny) and Tenny (E.E. Clive) so he can finally marry Phyllis (Louise Campbell). However, a evil (if somewhat inept) group of plotters are planning to steal a terrible new explosive and of course Drummond and company get dragged into Neilson's (John Barrymore) case.
The gang steal a suitcase of the explosive from an aeroplane but the suitcase ends up in Drummond's hands. The gang steals it back but everyone ends up on the same boat train to Paris for confusing escapades on a train and then a boat...
A good fast paced adventure though containing nothing you haven't seen before (especially if you have seen other films in the series). The character ensemble perform their usual quips or faints. A perfectly enjoyable film.