Capt. Jim Hollenbeck (Guy Madison), a dedicated physician assigned to the space branch of the United States Air Force Medical Corps, voluntarily undergoes jump school training. He wants to better analyze the effect of parachute jumps on the human body. After jump school, Lt. Col. Masters (Walter Coy), the head of the space program, sends Jim to Sovern Air Force Base in Florida to evaluate a problematic, experimental ejection seat.