Georgi Flerov is a young Soviet physicist who needs a hobby. Well, a better hobby than frantically trying to read articles in the library about fission, because in early 1942, these articles cease to be found anywhere.
Flerov realizes that the lack of articles on uranium fission isn't due to lack of interest—on the contrary, he knows that it's because it's now considered top secret and very important.
He's even more worried about Germany's progress in creating an atomic bomb, especially because they have a ton of uranium ore in addition to "first-class scientists."
The Soviets really need to start their own atomic bomb program. Unfortunately, though, they are preoccupied with fighting off the German invasion—so if they're going to get an atomic bomb, they're going to have to steal it.
By March of 1942, Semyon Semyonov and his fellow KGB agents are on the case, trying to cultivate spies in America in order to steal information regarding the atomic bomb.
A KGB courier named Zalmond Franklin (you keeping these guys straight?) gets a lucky break when he gets dinner with an old friend, Clarence Hiskey, who blurts out—like an idiot, if you ask us—that he's working on an atomic bomb.
Vasily Zarubin, top KGB agent in New York, telegraphs Franklin's report to HQ in Moscow. Moscow is like, "Duh—go back and get all the information you can."
Fortunately for us, when Franklin goes to have dinner with Hiskey (to try to pump him for information), Hiskey's wife is present the whole time, which prevents him from asking any pertinent questions.
Hiskey is subsequently transferred to the University of Chicago. When a Soviet agent tries to meet with him there, the FBI is all over it—next thing Hiskey knows, he's drafted into the army and shipped to a remote military base in the Northwest Territories of Canada. Boom. Problem solved.
Stealing information about the atomic bomb is such a big priority to the Soviets that the project is code named "Enormoz," which is Russian for enormous.
Step One for Enormoz is to cultivate any American scientists with ties to the bomb project who might be sympathetic to the communist cause. Numero Uno on their list of desirables is Robert Oppenheimer.