On the Threshold of Space

On the Threshold of Space (aka Threshold of Space) is a 1956 drama directed by Robert D. Webb, starring Guy Madison, Virginia Leith and John Hodiak. It was Hodiak's final film; he died six months before it was released. On the Threshold of Space provides a historical depiction of air force tests made in the United States for the imminent space race. Plot 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 Air Force Base in Florida to evaluate a problematic experimental ejection seat. While ejecting from his aircraft, test pilot Mike Bentley (Warren Stevens) broke his shoulder. Jim is assigned to determine what happened. In a test, when his arm is also broken, Jim determines that the wind blast during ejection forced his arm off the ejection release. Once the seat mechanism is modified, a series of tests at supersonic speeds are begun with rocket sleds launched at 1,000 miles per hour. Dr. Hugh Thornton (Dean Jagger) head of the program and Jim's mentor, wants Jim to test the first balloon gondola designed to carry a man 20 miles up into the "threshold of space," the first step toward putting a man into space.