William WindomMajor Rick Graves William WoodsonNarrator (voice) (uncredited) Michael RennieVice Chancellor Pierre Alquist Lin McCarthyCol. Archie Harmon Simon ScottMaj. Pete Stanhope Richard O'BrienBrother John Byron KeithGen. Cullenbine John MilfordSheriff Lou Carver Hal TaggartPedestrian (uncredited) Ron NymanAlien (uncredited) Dabney ColemanJohn Carter William SargentDr. John Devin Laurence NaismithCyrus Stone Patricia SmithSally Palay Robert KnappLt. Col. Howell James T. CallahanDr. Harry Mills Lew BrownNon-Com in Charge Dallas MitchellJim Rogers Robert SorrellsDeputy Jim Douglas HendersonLieutenant Farley Ford RaineyGen. Jonathan Blaine Barney PhillipsEmmett Morgen Suzanne PleshetteAnne Gibbs William SmithersAdam Lane Katherine JusticeJanet Garner Peter Mark RichmanAndrew Hatcher Johnny JensenFrankie Reed Robert H. HarrisDr. Stanley Frederickson Craig ChudyAlien (uncredited) Joanne LinvilleProf. Pat Reed John ZarembaProfessor Ed Harrison Lee FarrJustice Department Agent Michael HarrisMail Truck Driver Paul ComiPolice Sgt. Leeds R.G. ArmstrongPolice Capt. Bill Battersea Rayford BarnesAlien Driver Eduard FranzPremier Thor Halvorsen Ted KnightAlien Narrator (uncredited) Dan FrazerReporter (uncredited) Roddy McDowallLloyd Lindstrom Willard SageLieutenant James Jackie KendallProprietress Stuart LancasterSuperintendent Diana Van der VlisEve Doneghan Arthur HillWarren Doneghan Carol Eve RossenSelene Lowell Jonathan GoldsmithKevin Ryan Phillip PineSgt. Hal Corman Robert EmhardtOliver Ames Kathleen WiddoesEllen Woods Jeanette NolanMiss Havergill William BramleyConstable Gabbard Jim HalfertyFred Danielson Andrew DugganGeneral Theodore Beaumont Robert OsterlohCarl Wyeth Rick MurrayParking Attendant James WhitmoreHarry Swain William TalmanColonel Griffith Milton SelzerA.J. Richards Susan StrasbergDiane Oberly Ernest SarracinoLeo Rinaldi Robert DoyleSgt. Walter Ruddell Murray MathesonDr. Reynard Jacqueline MayoSobbing Woman Nancy WickwireEvelyn Bowers Ron StokesAlien at Controls Joseph CampanellaFather Joe Robert Walker Jr.Nick Baxter Lynn LoringMadeline Flagg Joseph V. PerryJoe Bagely Len WaylandDeputy Wallace Mercedes ShirleyWoman Attendant Ralph ThomasDeputy in Charge Strother MartinCharlie Coogan John LuptonMaj. Clifford Banks Andrew J. McIntyreDirector Of Photography Meredith M. NicholsonDirector Of Photography 
