10 Storylines You Can Expect to See During This Is Us Season 3

The show's creator Dan Fogelman told Entertainment Weekly that Jack's backstory will be explored more in season three, including his time in Vietnam. "In many ways, Jack might be the character we still have the most to learn about, because he's kept so many secrets in this period before we've really know him," he said. "[Now], we can do things with Jack and learn things about Jack that we really can't with a lot of our other characters."