Andrew Marton Director, Producer Lloyd Bridges Dr. Doug Standish Actor Shirley Eaton Dr. Margaret E. "Maggie" Hanford Actor Brian Kelly Dr. Craig Mosby Actor David McCallum Dr. Philip Volker Actor Keenan Wynn Hank Stahl Actor Marshall Thompson Dr. Orin Hillyard Actor Gary Merrill Dr. August "Gus" Boren Actor Ron Hayes Brinkman Actor George Shibata Prof. Uji Hamaru Actor Frank Logan Captain of the Diligence Actor Don Wells Sonar Man Actor Donald Linton Vice President of the USA Actor George De Vries Coast Guard Lieutenant Actor Tony Gulliver Officer Actor Joey Carter Technician Actor Celeste Yarnall Secretary Actor Paul Gray Pilot Actor Arthur Weiss Screenwriter Art Arthur Screenwriter Ivan Tors Producer Clifford Poland Cinematographer Warren Adams Film Editing Harry Sukman Original Music Mel Bledsoe Art Director Preston Rountree Art Director Max Pittman Set Decoration