In the late 1960s, astronauts training in an Apollo simulator have their session ended early. They grumble about it, but their commander, Chiz (Robert Duvall), knows the reason for the abort: the Pilgrim Program. The Russians will be sending a moon landing mission up in four weeks. The Americans had a secret alternate plan to the Apollo program (Pilgrim) in case this happened. One man would be sent to the moon in a one-way rocket, a modified Project Gemini craft. He would stay on the moon for a few months in a shelter pod launched and landed before him. Later, a manned Apollo mission would come to retrieve him.
The equipment is ready, but the Russians complicate matters by sending up a civilian. Chiz, although trained and qualified, is an Air Force colonel. NASA and the White House insist that an American civilian be their first man on the moon. Lee (James Caan), one of Chiz's crew, is tapped. Chiz is outraged, but agrees to train Lee in the few days they have. Chiz pushes Lee's training hard, half to get him ready, half hoping he will drop out and Chiz can step in. Lee persists, driven by the same astronaut dream.
After a press leak about Pilgrim, the Russians launch a week early. Deflated at not being first, everyone carries on. The shelter pod (a LEM lander) is launched and landed successfully. Lee is launched on schedule. He encounters a power drain malfunction en route which tests his character and hinders radio contact. The Russians have also lost contact with their team. As Lee orbits the moon, he does not see the beacon of the shelter. With only seconds left before he must abort and return to Earth, he lies about seeing it. Mission Control okays his retro burn and he lands. Now all radio contact is lost. Lee gets out of the Gemini lander and walks around with three hours of oxygen in his suit. He finds the crashed Russian lander on its side, the three dead cosmonauts sprawled around it.
Everyone on Earth is nervously awaiting news, but none comes. Lee takes the Soviet flag from a dead cosmonaut and lays out the Soviet flag on a nearby rock with his own American flag. With little air left and nowhere to go, Lee spins the toy mouse his son gave him. It points right, so he walks in that direction. People on Earth are losing hope as his time has run out. Lee looks at his watch to see that he has just minutes of air left. A red glow on his arm catches his attention. It is the locator beacon atop the shelter. Lee is last seen walking towards the shelter and survives.James Caan as Lee Stegler
Joanna Cook Moore as Mickey Stegler (as Joanna Moore)
Robert Duvall as Chiz
Barbara Baxley as Jean
Charles Aidman as Gus
Steve Ihnat as Ross Duellan
Michael Murphy as Rick
Ted Knight as Walter Larson
Stephen Coit as Ehrman
John Rayner as Dunc
Charles Irving as Seidel
Bobby Riha as Stevie Stegler
Countdown benefited from the cooperation of NASA, lending facilities to enhance the production. Altman was fired as director of the film for delivering footage that featured actors talking over each other. While this went on to be a signature invention of Altman, it was so new that studio executives considered it incompetence rather than an attempt to make scenes more realistic. In the documentary "Altman," the director explains that he was "just trying to get the illusion of reality" but that he was fired for "overlapping dialogue."
In a May 1968 review for The New York Times, critic Howard Thompson calls the film a "limp space-flight drama" which "makes the moon seem just as dull as Mother Earth". A February 1985 review in Malaysia's New Straits Times calls Countdown "dated" and complains that the characters have "no depth or direction". In a June 1995 story on the history of spaceflight movies, Thomas Mallon appreciates that the film "highlights the space program's early can-do ethos" but calls it a "little movie" with "few touches of Mr. Altman's later cynical wit" and "somehow not terribly suspenseful".
A comic book adaptation of the film was published by Dell Comics in October 1967.