It's 1959 and Russia is winning the space race. In order to compete, The United States forms NASA and chooses to recruit the nations best test pilots to form what will become the Mercury Astronauts. Among these test pilots are the golden boy John Glenn, the reckless Alan Shepard, and Gordo Cooper, whose broken marriage could cost him a place at the program.

After mysterious bouts of vertigo, Shepard turns to Dee O'Hara to help him. Meanwhile, Cocoa Beach has transformed from ghost town to perpetual party. Gordo finds himself tempted by another woman. Glenn seeks refuge from the bedlam at a local church gathering, where even he is confronted by temptation. The astronauts' families arrive in Florida to watch the first test launch of the Atlas Rocket.