Entertainment TV The Most Explosive Fan Theories About Jack's Death on 'This Is Us' The cause of his death, however, remains a mystery, so fans have taken to the Internet to share their theories By Maria Yagoda Published on February 15, 2017 03:07 PM Share Tweet Pin Email Photo: Vivian Zink/NBC/NBCU Photo Bank via Getty Images On the fifth episode of This Is Us, the tear-jerking NBC drama confirmed that patriarch Jack Pearson dies. The cause of his death, however, remains a mystery, so fans have taken to the Internet to share their theories, based on the flashbacks we see of Pearson, played by Milo Ventimiglia, from the ’80s. While Mandy Moore, who plays his wife Rebecca, tells TVGuide.com that the circumstances surrounding Jack’s death won’t be revealed for a “long, long time,” that hasn’t stopped the speculation. Here are some of the most explosive fan theories of how Jack died. 1. He died in 9/11.http://just-an-outlaw.tumblr.com/post/156202168931/i-just-read-the-best-theory-on-jacks-death There is just one flaw to that theory: Kate said they watched the Super Bowl together in 2006. 2. Miguel killed him. Even Miguel himself, a.k.a. Jon Huertas thinks this notion is bonkers. “What kind of show are you watching?” he asked fans and laughed during an interview with Entertainment Tonight. “This isn’t a murder mystery.” 3. Rebecca was in on his murder. 4. He died while drunk driving. 5. He dies while Rebecca is on tour, possibly by committing suicide. RELATED VIDEO: Chrissy Metz Talks Being a Role Model for This Is Us Fans Struggling with Their Weight As sad as it is that Jack will be dying at some point during the season, Ventimiglia urges fans to appreciate the time they have with him. “I just said: ‘Guys, just wait. Jack’s journey is not over. Jack is still going to be there, but you also know now how important these moments are with his wife, with his kids,’” he told PEOPLE after the big reveal. “He doesn’t know that he’s going to be passing at a certain age.” This Is Us airs Tuesdays (9 p.m. ET) on NBC.