Arnold Laven
Director Arthur Gardner
Producer Jules V. Levy
Producer

Tim Holt
Lt. Cmdr. John 'Twill' Twillinger Audrey Dalton
Gail MacKenzie Hans Conried
Dr. Jess Rogers Barbara Darrow
Jody Simms Max Showalter
Dr. Tad Johns Harlan Warde
Lt. Robert 'Clem' Clemens Gordon Jones
Sheriff Josh Peters Mimi Gibson
Sandy MacKenzie Marjorie Stapp
Connie Blake Jody McCrea
Seaman Fred Johnson Wallace Earl
Sally Dennis McCarthy
George Blake (lab assistant)

David Duncan
Story Heinz Roemheld
Conductor Joel Moss
Sound Recordist Charles Althouse
Sound Recordist Pat Fielder
Screenplay Lester White
Director of Photography John Faure
Editor Scotty Welbourne
Underwater Director of Photography Paul Eagler
Other B. F. Remmington
Sound Recordist