A gang of Cockney lads discovers that their favorite comic paper has become the vehicle for coded information being passed by crooks. Scotland Yard refuses to take the affair seriously, but the author of the adventure stories, a bookish, squeamish and reclusive Alastair Sim, is harassed into the chase which climaxes brilliantly in a riverside bomb-site.
“Quite possibly, the first ‘genuine' Ealing comedy. For a full appreciation of the near-plausibility of its plot, one needs to comprehend the enormous influence of comic-papers on British youth in pre-TV days.... though in a sense it is the same influence that TV exerted later. The rollicking schoolboy-melodrama plot is in much the same vein as the classic German ‘Emil and the Detectives,' and it is helped immeasurably by much on-location shooting in London, and by some inventive casting against type with at least two of Ealing's most stalwart policeman-detective regulars playing villains. Sim is there partly for box office insurance and his role is relatively minor, but he makes more than the most of his bravura sequences.”