Forty-something Gary, Simon and Cindy are colleagues at a stockbroker firm. While surfing on his high school alumni page, Gary notices the profile of his ex-girlfriend Jennifer, whom he hasn't seen in twenty years.
Coincidentally, Jennifer happens to be Cindy's friend. After helping Jennifer join their firm, Gary tries to get back with her, but she feels that there is no more chemistry.
Against Cindy's advice, Jennifer begins looking for love in all the wrong places, while Gary embarks on a mission to win Jennifer's heart back. Encouraged by tech-savvy Simon, Gary decides to sabotage her attempts to find a boyfriend by hacking into her computer, voice mail and cell phone.
As his obsession escalates, his actions become increasingly extreme.