Watch a nearly naked Milo Ventimiglia recreate Jack's 'birthday suit' scene in This Is Us finale

This Is Us type TV Show network NBC Where to watch Close Streaming Options

When This Is Us unveils its final episode of the season on Tuesday night, you're going back to where it all began.

This Is Us launched in the fall of 2016 with a new take on the family drama, a twist for the ages and, yes, a nearly naked Milo Ventimiglia, his front side shielded only by a Pittsburgh Steelers Terrible Towel. The season 4 finale, which airs Tuesday night, will further the adventures of the Pearsons, and also pay homage to that very first episode, as Jack (Ventimiglia) now celebrates his first birthday after the Big Three were born. He dons his "birthday suit" — towel in effect, once again — in hopes of a sexy celebration with wife Rebecca (Mandy Moore), who's carrying a cupcake with a candle. But before the fun can begin, three 1-year-old infants who are also celebrating their birthday have a different idea. Check out this exclusive preview above.

And, yes, there's a whole lot more going than an early '80s birthday. In the present day, the Pearsons are gathering in L.A. to celebrate the first birthday of baby Jack, and there will be repercussions for Randall (Sterling K. Brown) oping to strong-arm Rebecca into enrolling in the Alzheimer's clinical trial in St. Louis. Does that mean that you will find out how Randall and Kevin (Justin Hartley) wound up not speaking by their 40th birthday? It means exactly that. And to see what else the This Is Us producers teased about the season finale — and their thoughts on Randall's 'divisive' phone call to Rebecca — head over here.

"Strangers: Part Two" airs Tuesday at 9 p.m. on NBC.

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