Doppelgänger

“You will meet yourself face-to-face when Earth meets its duplicate in outer space!”

Colonel Glenn Ross (Roy Thinnes) is an American astronaut with a wife, Sharon (Lynn Loring), waiting at home. He is chosen for a European space mission to a planet hidden on the far side of the sun, in the same orbit as Earth. Robert Parrish sends him there beside the British scientist John Kane (Ian Hendry), and the long flight leaves the two men alone together.