AnalienstarshipcrashesinaswampinaU.S.NationalPark.Somemosquitosbegintofeedfromthealien'scorpses, causingthemtogrowtothesizeofavulture.Thesemutantinsectsbecameveryagressive, killingeveryhumanbeingtheyfind.Willthefewsurvivorsfightsuccessfullyagainstthisnightmare...?