Justin Hartley: 'This Is Us' Fans Will 'Never Guess' How Jack Dies

Justin Hartley isn’t sure This Is Us fans are ready to find out how Jack (Milo Ventimiglia) dies in the show.

In fact, he has yet to see a correct fan theory about the death of his on-screen father.

“You’ll never guess it,” Justin told Us Weekly. “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.”

Pictured: Justin does some press on Wednesday (February 22) in New York City.

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