Giants Mollusks are released from the earth by an earthquake and start killing people.
Tim Holt
as Lt. Cmdr. John 'Twill' Twillinger
Audrey Dalton
as Gail MacKenzie
Hans Conried
as Dr. Jess Rogers
Barbara Darrow
as Jody Simms
Max Showalter
as Dr. Tad Johns
Harlan Warde
as Lt. Robert 'Clem' Clemens
Gordon Jones
as Sheriff Josh Peters
Mimi Gibson
as Sandy MacKenzie
Marjorie Stapp
as Connie Blake
Jody McCrea
as Seaman Fred Johnson
Wallace Earl
as Sally
Dennis McCarthy
as George Blake (lab assistant)
