In a bombed-out post-war London neighborhood, a tight-knit group of teenage readers—the Blood and Thunder Boys—find solace in illustrated adventure stories from British boys’ magazines. Their leader, Joe Kirby, Harry Fowler, notices a troubling pattern: the very plots they read are being copied by a local crew who are rehearsing real-life robberies.
Joe takes the matter to the police, first approaching Inspector Ford, Jack Lambert, who treats the tip with a blend of humor and doubt. Yet Joe remains convinced something more is going on, so he brings the concern to his boss at work, Mr. Nightingale, Jack Warner. Nightingale’s curt reaction—to tell Joe to forget it—only steels Joe’s resolve rather than dulling his suspicion.
Resolute, Joe and another boy seek out the magazine’s reclusive author, Wilkinson, Alastair Sim. Inside Wilkinson’s world, they discover that the author’s carefully crafted wording is being altered somewhere between the drafting desk and the printing press. This strange redirection points to a controlled flow of information rather than random crime, and it becomes clear to the boys that the crimes are tightly tied to the stories they adore.
Their investigation narrows to a female employee of the publishing house, whom they track to a handsome suburban home in Hampstead. The confrontation is tense but unproductive; the woman offers no clear answers, and the trail seems to stall. Undeterred, the boys keep digging and eventually identify the drop location where the robbers stash their loot.
To turn the tables, the boys enlist Wilkinson’s help to craft a brand-new adventure tale—one designed to shepherd the criminals into a trap at the drop. The plan hinges on shifting the criminals’ expectations just enough to draw them out into the open, a narrative ruse that could expose the entire operation without tipping off the police too soon.
Joe then reports the evolving plan to Nightingale, only to realize—too late—that the man he trusted as his boss is, in fact, the mastermind behind the local crimes. The revelation reframes the entire operation: the supposed conflict between a boyish imagination and a criminal conspiracy is really a calculus of risk and power, with Nightingale as the architect behind the mischief.
The warehouse where the loot is kept becomes a stage for confrontation. A cache of fur coats and other pilfered goods is discovered, and Nightingale himself arrives with menacing intent. He threatens Joe, but the moment spirals into chaos as other crooks and toughs join the fray. Before order can fully take hold, hundreds of city boys answer a radio plea for help and surge into the scene, transforming the confrontation into a broad, boisterous showdown. Pandemonium gives way to the arrival of the police, who restore order and reclaim the situation.
In the aftermath, Joe tracks Nightingale to a bombed, multi-story building. What follows is a tense pursuit and a decisive showdown, culminating when Nightingale plunges through a floor hole, bringing the immediate danger to a dramatic close. The city’s wide-eyed youth, the mastermind’s fall, and the arrival of law enforcement converge to restore a fragile peace to the neighborhood, leaving the teens with a sense that stories—real and imagined—can shape outcomes as surely as any crime.
