Sean Connery (Dr. Paul Bradley), Natalie Wood (Tatjana Donskaja), Karl Malden (Harry Sherwood), Henry Fonda (Der Präsident), Trevor Howard (Sir Michael Hughes), Martin Landau (Gen. Barry Adlon), Brian Keith (Dr. Alexej Dubow), Joseph Campanella (Easton), Katherine DeHetre (Jan), Richard Dysart (Secretary of Defense), Bo Brundin (Rolf Manheim), James G. Richardson (Alan Marshall), Roger Robinson (Bill Hunter), Michael Zaslow (Sam Mason), John McKinney (Peter Watson), John Findlater (Astronaut Tom Easton), Paul Tulley (Astronaut Bill Frager), Allen Williams (Astronaut Michael McKendrick), Bibi Besch (Helen Bradley), Gregory Gaye (Russian Premier), Clyde Kusatsu (Yamashiro), Burke Byrnes (Coast Guard Officer), Joseph G. Medalis (Bartender), Charles Bartlett (Guard), Raymond O'Keefe (Guard), Henry Olek (Army Captain), Peter Bourne (UN President), Stanley Mann (Canadian U.N. Representative), Ronald Neame (British U.N. Representative), Philip Sterling (Russian U.N. Representative), Arthur Adams (Ghana U.N. Representative), Fred Carney (United States U.N. Representative), Sybil Danning (Swiss Girl Skier), Meschino Paterlini (Swiss Boy Skier), Johnny Yune (Siberian Man), Eileen Saki (Siberian Woman), Christine Anne Baur (Communications Center Technician), Paul Camen (Communications Center Technician), Dorothy Catching (Communications Center Technician), Bill Couch (Communications Center Technician)