Lindy Sampson is a daring and brilliant 21-year-old hacker who's come to New York City to search for her abducted sister. But when Lindy's best friend signs her up for a dating app in an attempt to pull her out of her shell, Lindy begins to suspect that one of the guys she just met may be a dangerous stalker. Now, to find out which date is stalking her, Lindy will need to enlist the help of the ex-boyfriend who betrayed her and broke her heart.