Chief of the U.S. Manned Space program, Charles Keith (Gregory Peck), awaits the return to Earth of the Ironman One spacecraft. When the ship misfires during re-entry, its crew -- Commander Jim Pruett (Richard Crenna), scientist-astronaut Clay Stone (James Franciscus) and pilot Buzz Lloyd (Gene Hackman) -- are left marooned in space. And as Keith and senior astronaut Ted Dougherty (David Janssen) initiate a desperate rescue plan, the world -- and the astronaut's wives -- can only watch and wait.