In San Jose, California, David Kim looks through old photographs and videos of his daughter Margot and his late wife Pamela, who died from lymphoma nearly two years earlier, after which David and Margot became distant. One night, Margot goes to a friend's house for her study-group. The next morning, David is unable to reach Margot but assumes she has risen early to go to school. Later, he calls Margot's piano instructor, but is informed that Margot had canceled her lessons six months ago. David discovers that Margot had been pocketing the money for the lessons, before suddenly transferring $2,500 to a deleted Venmo account. Realizing that Margot is missing, David calls the police, and the case is assigned to Detective Rosemary Vick, who asks for information about Margot's personality and friendships. David manages to access Margot's Facebook and speaks to her contacts only to discover that Margot has not had close friends since Pamela's death.