THE INSTANT #1 NEW YORK TIMES BESTSELLER!A Most Anticipated Book by Today ∙ Oprah Daily ∙ Katie Couric Media ∙ BuzzFeed ∙ SheReads ∙ Zibby Mag ∙ PopSugar ∙ BookRiot ∙ Culturess ∙ Her Campus ∙ The Everygirl ∙ and more!A random connection sends two strangers on a daylong adventure where they make a promise one keeps and