Theodore Hall is a genius. He enters college at the age of fourteen, and by eighteen he's graduating from Harvard with a degree in physics.
Hall gets recruited right before graduation by a mysterious ex-professor who now works for the government. Gee, who could that be?
His roommate, Saville Sax, is a dedicated communist, and he tells Hall that whatever the project is, he should tell the Russians about it.
Hall goes to Los Alamos where he's assigned to work on a team led by Bruno Rossi to determine how much U-235 would be needed to make a uranium bomb.
Oppenheimer receives the first samples of plutonium at Los Alamos.
Crisis ensues when, after a few experiments, the scientists realize that their plan for a gun-assembly method of deploying a plutonium bomb doesn't work because it fissions too fast. So now, if they're going to have more than one atomic bomb in the near future, they need to work out an entirely new design for the plutonium version. It's back to the drawing board.
Ted Hall continues to impress the other older, more experienced scientists by thinking outside the box.
He also has a lot of sympathy for the Soviets.
More importantly, Ted Hall believes that it would be more dangerous for only one country to have atomic bombs than just the wrong country having them. So he decides to contact the Soviets and share information with them to prevent an American monopoly on atomic weapons.