Peter Graves as Dr. Ed Wainwright

Peggie Castle as Audrey Aimes

Morris Ankrum as Gen. John Hanson

Than Wyenn as Frank Johnson

Thomas Browne Henry as Col. Tom Sturgeon

Richard Benedict as Cpl. Mathias

James Seay as Capt. James Barton

John Close as Maj. Everett

Don C. Harvey as State Police Car 254 Officer

Larry J. Blake as Roadblock Sergeant

Eilene Janssen as William's Date

Hyllton Socher as Frank, grainary platoon soldier

Frank Wilcox as Gen. Short

Douglas Evans as Editor Norman Taggart

Paul Grant as William Summerfield, teen boy

Richard Emory as Lieutenant

Hank Patterson as Dave

Steve Warren as Observation Post #3 Soldier

Frank Connor as Observation Post #1 Soldier

Don Eitner as Observation Post #2 Soldier

Rayford Barnes as Chuck, granary platoon soldier

Kirk Alyn as Bomber Pilot

Bill Baldwin as TV Announcer (uncredited)

Frank Chase as Helicopter Pilot (uncredited)

Joe Cranston as Soldier (uncredited)

Patricia Dean as Red Cross Representative

James Douglas as Army Sentry (uncredited)

Paul Frees as Helicopter Pilot (voice)

Lyle Latell as Police Lt. MacKenzie (uncredited)

Dennis Moore as Police Dispatcher KLP646

Zon Murray as Roadblock Sentry Confiscating Camera

Alan Reynolds as Agricultural Agent

Ralph Sanford as Man with Red Cross Representative [extra]

Bert Stevens as Col. Hill [bit]

Alan Wells as Headquarters Sergeant