James Whitmore .... Sergeant Ben Peterson

Edmund Gwenn .... Dr. Harold Medford

Joan Weldon .... Dr. Patricia "Pat" Medford

James Arness .... Robert Graham

Onslow Stevens .... Brigadier General O'Brien

Sean McClory .... Major Kibbee

Chris Drake (I) .... Trooper Ed Blackburn

Sandy Descher .... The Ellison Girl

Mary Alan Hokanson .... Mrs. Thomas Lodge

Don Shelton (I) .... Trooper Capt. Fred Edwards

Fess Parker .... Alan Crotty

Olin Howlin .... Jensen

Runtime: USA:94

Country: USA

Language: English

Color: Black and White

Sound Mix: Mono

Certification: Australia:PG / Finland:K-12 / Germany:12 / USA:Unrated (probably would be PG)

Go to IMDB for the rest