In the early hours of the night, young David Maclean sees a flying saucer land and disappear into the sand dunes just beyond his house. Slowly, all of the adults, including his once loving parents, begin to act strangely.

From the trial of the survivors, we flash back to amoral crook Ralph Cotter's violent prison break, assisted by Holiday Carleton, sister of another prisoner...who doesn't make it. Soon Ralph manipulates the grieving Holiday into his arms, and two crooked cops follow her into his pocket. Ralph's total lack of scruple brings him great success in a series of robberies. But his easy conquest of gullible heiress Margaret Dobson proves more dangerous to him than any crime...