'This Is Us' Reveals a Monumental Clue About Jack's Death

WARNING: Spoilers ahead for the Season 2 premiere of This Is Us! Continue reading at your own risk...

This Is Us has kept Jack's death a mystery since its series premiere last fall, and fans are anxiously waiting to find out exactly what happened to the Pearson family patriarch.

In tonight's season premiere, fans finally found out what caused Jack's death.

At the end of the episode, the kids were seen with Miguel, finding out that their father had died. Kate told Randall that she needed to find Kevin and tell him what happened.

Rebecca pulled up to their house and began crying, as she saw that most of the house was burnt to the ground.

Earlier in the episode, it was revealed that Jack's death came not long after the big fight. The kids were 17 years old at the time.

As Kate is at a vocal audition, Toby and Kevin sit in the lobby and talk. Kevin admits that Kate is the one who told him about his father's death.

While this may have revealed the cause of Jack's tragedy, there is still plenty to learn about that fateful night.

The mystery will continue to unfold as This Is Us Season 2 continues this fall.