Dr. Jeffrey Stewart
Dr. Dan Forbes
Connie Stewart
Dr. Allard
Dr. Benton
Howard Denker
Mr. Simon
Dr. Serny
Chief Watson (as John Zarimba)
City Engineer
Mayor
Gen. Behan (as Roy Engle)
Col. Willis
Capt. Dyer
Dr. Carthwright
Cabbie (as Charlie Williams)
Kenneth Smith
Albert (as Bill Benedict)
Nelly
Pilot
Co-Pilot
Stewardess
Joy
Spinster
Airline Pilot (uncredited)
Nova Scotia Lab Worker (uncredited)