Hannah Upp had been missing for nearly two weeks when she was seen at the Apple Store in midtown Manhattan. Her friends, most of them her former classmates from Bryn Mawr, had posted a thousand flyers about her disappearance on signposts and at subway stations and bus stops. It was September, 2008, and Hannah, a middle-school teacher at Thurgood Marshall Academy, a public school in Harlem, hadn’t shown up for the first day of school. Her roommate had found her wallet, passport, MetroCard, and cell phone in her purse, on the floor of her bedroom. The News reported, “Teacher, 23, Disappears Into Thin Air.”