How to Follow Strangers

A young man, obsessed with the true story of a woman who died in her apartment and remained undiscovered for over a year, fakes his own disappearance in the hopes of finding out who will notice. His vanishing act sparks the attention of Ellie, a young woman who shares a daily commute, who decides to find out where he's gone, setting off a series of incidents that will bind them together. (FilmBuff)