Lauren Groff, Elizabeth Kolbert, Pam Houston, Pico Iyer, T Kira Madden, Gregory Pardlo, Maggie Shipstead, and Peter Orner are among the 65 writers who grapple with this mystery: How can an ephemeral encounter leave an eternal mark? When Colleen Kinder put out a call for authors to “write a letter to a stranger who haunts you,” she opened the floodgates. These short, insightful essays by today’s best literary minds are organized around such themes as Grati­tude, Wonder, and Farewell, and guide us both across the globe and through the mysteries of human connection. These pieces are replete with observations about how to live and what to seek, and how a stranger’s loaded glance, shared smile, or question posed can alter the course of our lives.