In 1944, eighteen-year-old June Walker begins work with hundreds of other young women at a brand new factory with giant machines--but neither she, nor anyone else, is told what the facility is. Eager to know more, she begins an affair a young Jewish scientist named Sam Cantor who knows all to well what the facility is designed for. Meanwhile, an African American construction worker, Joe Brewer, doesn't care what the facility is, but knows it's paying the bills for his family in Alabama. Then, after a security breach, Joe and June's lives become intertwined.