The year is 1944.

The players are renowned sci-fi editor and sometimes-writer John W. Campbell, his buddy and fellow writer Cleve Cartmill, and the United States Federal Bureau of Investigations.

So Campbell and Cartmill coauthor a short story called Deadline that would be published in Campbell's magazine, Astounding Science Fiction-- which was a very well-known magazine among sci-fi fans and had featured such big name authors as Isaac Asimov, Robert Heinlein, L. Ron Hubbard.

Deadline is a story about a soldier named Ybor who has been dropped into enemy territory in order to infiltrate the enemy base and destroy the superweapon they're working on. The superweapon in question? An atomic bomb.

The story is basically golden age of sci-fi schlock, with Ybor immediately running into a beautiful fem-fatale, Ylas, who is also the director of an underground resistance allied with Ybor's people. Everybody has names like Sworb, Mulb, and Sleyg, there's a large chunk where Ybor and Ylas argue about who is actually an agent against the evil Sixa Alliance, and who is a dirty rotten faker trying to get the other one executed, there's a lot of plot contrivance relying on characters being imbeciles or having dumb luck, and writing like "a camaraderie had sprung up between them. He was male, not too long past his youth, with clear, dark eyes, and he was put together with an eye to efficiency; and she was female, at the ripening stage." Also, at some point, there's a blink-and-you'll-miss-it line referencing a character having a short, prehensile tail, so there's that.

The story can be read here.

The interesting bit comes in the latter half of the story, where Ybor encounters the Sixia scientist in charge of the superweapon, a new kind of bomb, and Ybor infodumps the mechanics of how the bomb works, with special mention to the use of uranium. Here's an excerpt:

Two cast-iron hemispheres, clamped over the orange segments of cadmium alloy. And the fuse–I see it is in–a tiny can of cadmium in a beryllium holder and a small explosive powerful enough to shatter the cadmium walls. Then–correct me if I’m wrong, will you?–the powdered uranium oxide runs together in the central cavity. The radium shoots neutrons into this mass–and the U-235 takes over from there. Right?

Zeph, you may say, that isn't interesting at all! Well, not to you or I, friend. But one party found it very interesting.

Some time after publishing the story, Cartmill got a knock on the door, and who should it be but the FBI.

Because, hey, apparently the US government was working on a little thing called The Manhattan Project, and the boring infodumps Ybor espouses were eerily close to the actual workings and predicted workings of the atomic bomb being developed, and included things such as the use of Uranium 235, a problem relating to isotopes the real scientists were struggling with, the size and temperature of a nuclear explosion, and the effects of radiation. In fact, the US Government was so concerned that there might have been a security breach that they hired Cartmill's postman to spy on him and report his mail.

Cartmill, upon being interrogated and accused of espionage, pointed the feds in Campbell's direction. While the work was a joint venture, Campbell was the one who wrote all the technical details relating to the bomb.

So the feds go and visit Campbell, and when asked how he knew so much about the bomb, he told them that he was an MIT graduate who had studied physics, had done a course or two specifically on atomic things, and who paid attention to scientific developments and discoveries--nonclassified ones in articles and journals freely available to the public. Campbell and Cartmill apparently were just two fuckin' science nerds who followed public scientific endeavors and put two and two together that people could make a super bomb, and because they were science nerds, they wrote about it in the most reasonable/realistic way possible-- which happened to be close enough to the truth to freak the FBI out.

Supposedly, the agents, eventually, believed that Campbell and Cartmill had stumbled into it all through sheer nerdery and instructed Campbell to stop writing about atomic bombs and the making of such until after the war was over.

Purportedly, Campbell also figured out that some big government science project was going on in Los Alamos (which was one of the bases building the bomb) because a shitton of his sci-fi magazine's subscribers suddenly changed their addresses and had their subscriptions sent to the middle of the freakin desert.