Without Warning (Greydon Clark/1980) Scream Factory Blu-ray released August 2014.

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Starring: Jack Palance, Martin Landau, Cameron Mitchell, Kevin Peter Hall, Neville Brand, Sue Ane Langdon, David Caruso & Ralph Meeker.

Four teenagers on a lake trip are warned of strange happenings occuring in the area they plan to visit.They ignore all warnings and are attacked by alien creatures.