A planet is discovered in the same orbit as Earth's but is located on the exact opposite side of the sun, making it not visible from Earth. The European Space Exploration Council decide to send American astronaut Glenn Ross and British scientist John Kane via spaceship to explore the other planet.
Roy Thinnes
as Colonel Glenn Ross
Ian Hendry
as John Kane
Patrick Wymark
as Jason Webb
Lynn Loring
as Sharon Ross
Loni von Friedl
as Lisa Hartmann
Franco De Rosa
as Paulo Landi
George Sewell
as Mark Neuman
Ed Bishop
as David Poulson
Philip Madoc
as Dr. Pontini
Vladek Sheybal
as Psychiatrist
George Mikell
as Captain Ross
Herbert Lom
as Doctor Hassler
