Margo Richter describes herself as an award-winning mobile app developer trapped in a 16-year-old girl’s body. As a Margo-centric teenager, she is laser-focussed on her own ambitious goals and her own busy life. A junior stuck in a freshman world history class, she is not the least bit interested in what is happening with those around her, much less those who lived hundreds or thousands of years ago. Why should she be? Her future is bright! This is Margo’s mindset before she is reluctantly thrown into the harried lives of teens living during the Black Plague, Chernobyl, Japanese Internment camps, Jesus’ crucifixion, the Wright Brother’s first flight, New York mafia, Auschwitz, the Titanic, the Great Depression and others. A seemingly simple assignment given by her world history teacher may significantly complicate her Margo-centric plans.