The Midwest USA is invaded by stingray-shaped alien slugs that ride on people's backs and control their minds in order to spread their dominion. Government agency reps Sam Givens, Andrew Nivens, and Mary Sefton must stop the aliens.
as Andrew Nivens
as Sam Nivens
as Mary Sefton
as Alex Holland
as Dr. Lawrence Graves
as Neil Jarvis
as President Douglas
as Ressler
as Viscott
as Culbertson
as Gidding
as General Morgan
as Greenberg
as Barnes
as Higgins
as Miss Haines
as Hawthorne
as Slugged Businessman (uncredited)
as Vince Hayward
as