The truth about Jack Pearson's ( "This Is Us." Justin Hartley (Kevin Pearson) previewed what's ahead for Papa Pearson, warning us we won't just be heartbroken, we'll also be surprised.

TMZ asked Hartley point-blank, "How did he die?" Of course, Hartley couldn't just go and spoil the fate of his on-screen father, but he did say this of Jack's fate:

"You'll find that out. And I'll tell you that it's absolutely heartbreaking and devastating and it's well worth the wait."

We're not expecting to wait too long. There are only two episodes left, and the season finale may be when we get the news. Many fans already have suspicions about how Jack died, but it's possible they're slightly or completely wrong.

Hartley basically told Us Weekly that we should expect to be surprised by the reveal:

"You'll never guess it. It's unexpected and it's extremely heartbreaking and sad and deep and moving and, ugh, it's painful. It's painful. It'll stay with you."

Ugh is right! The show's creator and an executive producer both recently teased what fans can expect in the final two episodes, and what will be held over for Season 2.

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