詹姆斯·惠特摩
James Whitmore
饰：Police Sgt. Ben Peterson
埃德蒙·格温
Edmund Gwenn
饰：Dr. Harold Medford
琼·韦尔登
Joan Weldon
饰：Dr. Patricia 'Pat' Medford
詹姆斯·阿尼斯
James Arness
饰：Robert Graham
翁斯洛·史蒂文斯
Onslow Stevens
饰：Brig. Gen. Robert O'Brien
肖恩·麦克洛里
Sean McClory
饰：Maj. Kibbee
克里斯蒂安·德雷克
Chris Drake
饰：Trooper Ed Blackburn
Sandy Descher
饰：The Ellinson Girl
玛丽艾伦霍坎森
Mary Alan Hokanson
饰：Mrs. Lodge
唐·谢尔顿
Don Shelton
饰：Trooper Capt. Fred Edwards
费斯·帕克
Fess Parker
饰：Alan Crotty
奥林·霍兰德
Olin Howland
饰：Jensen (as Olin Howlin)
马歇尔·布拉德福德
Marshall Bradford
饰：Psychiatrist (scenes deleted)
Richard Bellis
饰：Mike Lodge (uncredited)
约翰·贝拉迪诺
John Beradino
饰：Patrolman Ryan (uncredited)
Robert Berger
饰：Patrolman Sutton (uncredited)
Oscar Blanke
饰：Alcoholic Ward Patient (uncredited)
威利斯·布鲁辛
Willis Bouchey
饰：Official at D.C. Meeting (uncredited)
Richard Boyer
饰：Trooper #1 (uncredited)
Waldron Boyle
饰：Doctor (uncredited)
Alexander Campbell
饰：Official (uncredited)
詹姆斯·卡德韦尔
James Cardwell
饰：Officer (uncredited)
Royden E. Clark
饰：Jeep Driver (uncredited)
John Close
饰：Johnny, Police Aircraft Pilot (uncredited)
布思·科尔曼
Booth Colman
饰：Reporter (uncredited)
詹姆斯·科纳蒂
James Conaty
饰：Washington Official (uncredited)
Robert Scott Correll
饰：Jerry Lodge (uncredited)
沃尔特·科伊
Walter Coy
饰：Reporter (uncredited)
Dean Cromer
Dean Cromer
饰：MP Sergeant (uncredited)
理查德·迪肯
Richard Deacon
饰：Bald reporter, Los Angeles news conference (uncredited)
艾迪·朱
Eddie Dew
饰：Officer (uncredited)
劳伦斯·多布金
Lawrence Dobkin
饰：Los Angeles City Engineer (uncredited)
安·多兰
Ann Doran
饰：Child Psychiatrist (uncredited)
Wally Duffy
饰：Airman (uncredited)
Cliff Ferre
饰：Cliff, Police Lab Man (uncredited)
Norman Field
饰：Gen. James (uncredited)
Joseph Forte
饰：Coroner Putnam (uncredited)
Dean Fredericks
饰：Det. Curtis (uncredited)
Russell Gaige
饰：Coroner (uncredited)
Otis Garth
饰：Admiral at Second Conference (uncredited)
多萝西·格林
Dorothy Green
饰：Matron (uncredited)
Mary Lou Holloway
饰：Blonde (uncredited)
Gayle Kellogg
饰：Gunner (uncredited)
肯纳G.肯普
Kenner G. Kemp
饰：Trooper #2 (uncredited)
Hubie Kerns
饰：Jeep Driver (uncredited)
Warren Mace
饰：Radio Operator (uncredited)
Chad Mallory
饰：Loader (uncredited)
马修麦凯
Matthew McCue
饰：Gramps Johnson, Storekeeper (uncredited)
查尔斯梅瑞狄斯
Charles Meredith
饰：Washington Official (uncredited)
Forbes Murray
Forbes Murray
饰：Government Official (uncredited)
伦纳德·尼莫伊
Leonard Nimoy
饰：Staff Sergeant, Telex Operator (uncredited)
Jack Perrin
饰：Army Officer (uncredited)
Charles Perry
饰：Soldier (uncredited)
格兰丁·罗德
Grandon Rhodes
饰：Alcoholic Ward Doctor (uncredited)
乔·索耶
Joe Sawyer
饰：Capt. O'Connell (uncredited)
威廉·沙勒特
William Schallert
饰：Ambulance Attendant (uncredited)
Fred Shellac
饰：Attendant (uncredited)
Joel Smith
饰：Smitty, Ben's Jeep Driver (uncredited)
K.L. Smith
饰：Trooper (uncredited)
道格拉斯·斯宾塞
Douglas Spencer
饰：Reporter (uncredited)
Janet Stewart
饰：WAVE (uncredited)
Victor Sutherland
饰：Senator at D.C. Meeting (uncredited)
德博泰勒
Dub Taylor
饰：Railroad Yard Watchman (uncredited)
哈利泰勒
Harry Tyler
饰：Harry, Alcoholic Ward Patient (uncredited)
迪克·韦塞尔
Dick Wessel
饰：Railroad Detective (uncredited)
哈里·威尔逊
Harry Wilson
饰：Alcoholic Ward Patient (uncredited)
罗登·克拉克
Roydon Clark
Joan Weldon
饰：Dr. Patricia 'Pat' Medford