Dave Kroupa is surprised when his new girlfriend, Cari Farver, sends him texts with demands. When Dave ends the relationship, Cari sends him a lot of strange messages and then disappears. Liz, Dave's ex-girlfriend, also starts getting harassing texts from Cari, creating a dangerous situation for them both. Cari's mother, Nancy, keeps looking for her, putting pressure on the police, who eventually find something shocking.