In 1930s Los Angeles. Jack Parsons works as a janitor at a chemical factory by day, but, by night, he nurses a secret ambition: to build rockets that will take mankind to the moon. The pressures of his double life are further complicated when Jack and his wife Susan are confronted by a mysterious new neighbor, Ernest Donovan, who appears to be leading a double life of his own.

After Professor Mesulam gives his blessing to the project, Jack and Richard set off to create Caltech's first ever rocketry team. But Caltech's acceptance has come with caveats, and, coupled with Ernest's looming presence, Jack and Susan are feeling more on edge than ever before, desperate to figure out whether Ernest's intentions are evil or not.