Not far from the sun-kissed Santa Cruz beach where she had a traumatic childhood experience, the now-mother-of-two, Adelaide, reluctantly returns to their serene lake house with her husband, Gabe, to spend the summer vacation. However, after all this time, Adelaide still can't shake off the ominous feeling that the terrifying encounter with her bizarre doppelgänger will, somehow, come back to haunt not only her but also her unsuspecting family. Indeed, before the end of the day, the happy holidaymakers will see their worst fear come true, as an evil quartet who bears an uncanny resemblance to them stands in their driveway. Then, they pull out their sharp scissors. What do "they" want from them?