Stan Ulam is a 30-year-old talented Polish Jewish mathematician, a good-looking bon vivant who is quick with a joke. Stan's life becomes complicated when he loses his fellowship at Harvard but his best friend, the Hungarian genius Johnny von Neumann quickly offers him a mysterious job which takes him to New Mexico.
Stan moves to Los Alamos with Françoise, a French woman he meets and marries after a whirlwind romance. Surrounded by young, eccentric, charismatic immigrant scientists Stan begins top secret work on a nuclear bomb that could potentially blow up the entire world.
While desperately trying to help his sister flee Nazi occupied Poland, Stan teams up with Johnny to create the first computer giving birth to the digital age as Europe bursts into flames.