'This Is Us' Returns for Final Season, Sets Up Emotional Ending

It's the beginning of the end for the Pearsons as they kicked off the sixth and final season Tuesday.

Spoiler alert! Do not proceed if you have not watched Tuesday's final season premiere of This Is Us.

The Pearsons are back for one last hurrah.

This Is Us kicked off its sixth and final season Tuesday with an episode, titled "The Challenger" (a reference to the 1986 space shuttle disaster), that set in motion the family's final chapter. Much of the premiere teed up a lot of what we knew was coming -- Rebecca's deteriorating mental state, the gradual implosion of Kate and Toby's marriage (and the seeds of a new one with Englishman Phillip), Kevin and Madison's unraveling of their relationship, Randall's continued search for his identity -- and if it served as a preview for what the remaining 15 episodes will be, we're in for an emotional ride.

While there weren't many shocking revelations or reveals in the first installment of the outgoing NBC drama's last season, for the first time in its run, the episode offered the truest feeling of finality. That, in due time, the Pearsons' story was reaching the endpoint. In the episode, Rebecca struggled with the looming reality that her ability to remember even the smallest of memories -- namely a childhood one involving her father and the story of a red caboose -- are starting to fade and the severity of her sickness finally hitting Kate and Kevin.

And as Kate was acclimating to temporary single parenthood with Toby away at his new job, the very early seeds were being planted with the progression of Kate and Phillip's future relationship, the mystery of how she and the "English jerk" get together in the near future -- to the point of saying "I do," as revealed in the season 5 finale -- remaining one of the series' last mysteries to "solve."

Then there was Randall, whose past experience with a late-night break-in at his home a season ago, came unexpectedly back around. But not with the results he was hoping for. As Jack and Rebecca intimated in a flashback to the past, Randall's inkling to be everyone's guardian angel would break him time and time again. Sure enough, they were right. This time, Randall, who extended an olive branch to the guy who broke into his house instead of having him locked up, learned the hard way that not everyone is willing to take the high road. 

Kevin, meanwhile, faced a dilemma as he was (awkwardly) asked back to take part in a reboot of The Man-ny, the same sitcom he had a very public meltdown during years prior that nearly crippled his career. But, he discovered during his tense meeting with the same producer he went to blows with before, he wouldn't be playing the title character -- but the dad. His reluctance to accept the new job came as he and Madison struggled to navigate co-parenting their twins while no longer romantically involved. His decision to accept the not-so-enticing gig an effort to give financial stability to his unconventional modern family.

"I don't think there's any preparation," This Is Us star Milo Ventimiglia told ET's Denny Directo of the final season during a kick-off event in Los Angeles in December. "Just know it's coming. Know that you're probably going to get emotional. You're going to be upset about it. Just when somebody passes away or somebody moves on, you got a lot of good memories. I think it's good to have those memories to reflect on them, to watch the show if you wanted to, to share it. I think that's an important thing. What we've really managed to do with a piece of art, a TV show, [is] getting people to communicate and I hear that a lot when I'm out in the world and talking to people. Like, 'Hey, I talked to my mom. I haven't talked to my mom in a while,' or 'I called my brother up and we weren't doing so good.' I think the more that people can embrace that spirit of the Pearsons and actually transfer that into their own lives, what a nice impact."

"It is sad," Justin Hartley told ET of the end. "You get used to something, it's six years and it's seeing these people all the time for six years... And then you go, 'Well, we're not going to be doing that. We're not going to come to the studio. We're not going to be seeing each other. We're not going to be working on this project that we all love so much.' But the bond and the most important thing that you take from all these jobs that you do as an actor are the friendships and this group of friends has become a family honestly. They're my family so I'll keep in touch with every single one of them."

Added Sterling K. Brown, who described the final season as "unforgettable": "I'm excited. I'm all these things -- it's excitement, it's sadness, it's I'll have to say goodbye to my friends." He later advised that viewers will "need many boxes" of tissues to get through the season. 

Ahead of Tuesday's return, the cast and producers reflected on their whirlwind six-year journey as they kick-started their farewell.

Mandy Moore shared several throwback photos from over the years on Instagram, writing: "Looking back at my first days on set of every season of #ThisIsUs. 😍 Love that it’s always with @miloanthonyventimiglia (plus a cameo with @sterlingkbrown)!! Gonna miss these days with the fam when it’s all over, but for now, we get to come together (virtually of course) and watch the premiere ep tonight!!!"

Brown shared a GIF of a memorable season 1 scene between him and Hartley as he commemorated the beginning of the end. "This was @justinhartley and I earlier today after realizing the FINAL PREMIERE of #ThisIsUs is tonight!!!!!" he captioned on Instagram.

Hartley, meanwhile, went the comic relief route as he shared a photo from set in front of the infamous The Man-ny poster that served as his character, Kevin's, claim to fame. "Mondays may be 'Where Handsome Happens!', but Tuesdays are back tonight with #ThisIsUs!!!" the actor wrote.

Chrissy Metz was feeling nostalgic as she posted a series of photos on Instagram from the past five years of her with her fellow castmates. "Got the big three emotions while taking a trip down memory lane of some of my favorite memories… can’t believe the #ThisIsUsFinalChapter premieres tonight. Love you all," her note read.

Jon Huertas, who plays Miguel, also took to social media to celebrate the final season premiere.

And here is what executive producer/director Ken Olin and creator/executive producer Dan Fogelman had to say before the launch of the final season.

This Is Us airs Tuesdays at 9 p.m. ET/PT on NBC. For more, watch below.

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