'This Is Us' Calls Back to Series Premiere During Emotional Final Moments

This Is Us is all about how the events of the past and present connect and affect the future. On this week's episode, the show called back to one of the best moments in the series premiere.

This week's episode, "The Most Disappointed Man," featured a secondary past plot focusing on Randall's biological father, William. William is shown in court over a drug offense not long after he abandoned Randall.

A judge makes a deal with William that if he cleans up his act and stays off drugs, he will be let off. William agrees and seems to stick to his worries for most of his life.

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However, he starts to relapse after he receives his cancer diagnosis. He buys some heroin and sits down at his table to contemplate if he should use it.

As William begins to open the syringe packet, he is interrupted by a loud knocking on his door. He hides all the paraphernalia and answers the door. On the other side is Randall, who came to face his father for the first time.

Viewers will recognize the same exact interaction comes from the series premiere. Randall is determined to tell off his father and leave, but he ends up coming inside instead after a quick rant.

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This exact moment was a highlight in the premiere episode, and kicked off Randall's relationship with his now-late father. This added background makes the moment much more powerful, as it shows Randall saved his father from ending his life on a dark path.

This Is Us airs Tuesdays at 9 p.m. EST on NBC.