One of the most highly anticipated returns to television this fall is NBC's "This Is Us," which captivated hearts when it debuted in September last year. Since then, the show delivered a blow week by week, with shocking twists and turns that ultimately led to one big question—how does Milo Ventimiglia's Jack Pearson lose his life in the series? The fundamental question has led to multiple fan theories that involved drunk driving, terminal cancer, and even murder. None of these theories have been confirmed or denied by the cast and crew of the massively popular drama series, but one thing's for sure: fans will soon find out more about Jack's death when "This is Us" season 2 returns.

Mandy Moore confirms details of Jack's death in premiere

Singer and actress Mandy Moore, who plays Milo Ventimiglia's on-screen wife Rebecca on the series, recently spoke with Larry King about Jack's death, saying that the cast already knows the details about how he dies in the series. According to PEOPLE, the cast, in fact, knew it all along as "all of the core actors sort of had to know" because Jack's death "is something they’re going to carry with them as adults." Additionally, the actress said that the premiere episode of "This is Us" season 2 will tackle this right off bat, so that's something viewers will get to see a resolution to immediately. Now whether viewers are ready to find out the truth is another story, and true fans of the show should know to stock up on Kleenex while watching the series.

Actress opens up about 'effortless and palpable' chemistry with Milo Ventimiglia

Mandy Moore and Milo Ventimiglia are arguably one of the best couples on television today, as their chemistry translates well into how they play their characters. Despite Jack's death being revealed in the "This is Us" season 2 premiere, fans should expect to see more of the pair as they go through their married life together.

Moore recently opened up about Ventimiglia, sharing that knowing she was to work with him on the show made her want the part of Rebecca even more. According to Deadline, Moore credited their "effortless and palpable" chemistry for the way they've successfully shown both the highs and lows of marriage. She said, "It’s easy to understand the deep, kinetic love between them, but I’m happy that we have the opportunity to show a fully fleshed-out marriage of challenges and obstacles, too."

"This is Us" season 2 is set to return to NBC this fall.