This Is Us Season 6 Premiere Sets Up Rebecca's Heartbreaking Final Journey

[Warning: The following contains spoilers for the This Is Us Season 6 premiere. Read at your own risk!]

Welp, the time has arrived. The final season of This Is Us kicked off on Tuesday night and as expected, the beginning of the Pearson family's final chapter came with a mixed bag of emotions. The flashbacks focused on the day the Challenger space shuttle exploded and how the catastrophic news affected each of The Big 3. Young Kate decided to try and see the silver lining, young Randall focused on what the death of the astronauts meant for their kids left behind, and young Kevin entered a full existential crisis about death that went unnoticed by his parents. In the present, the Big 3 all reflected on how far they've come in the past five years — the show started following them on their 36th birthday and each of the siblings turned 41 in the episode — and the obstacles that lay ahead. 

However, the real emotional punch of the episode came from Rebecca (Mandy Moore), who revealed that a recent scan confirmed that plaque deposits were building in her brain, confirmation that Alzheimer's was beginning to set in. Throughout the episode, Rebecca struggled to remember what the word for the final car of a train was. She wouldn't let anyone give her the answer and spent her day at the park with her grandchildren trying to remember, and finally exclaimed at the Big 3 birthday party in frustration when she couldn't remember the word "caboose." That's when she revealed to her children that her tentative diagnosis of memory failure had finally become cemented. 

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Rebecca remembered the word caboose in the closing moments of the episode, withdrawing the word by remembering a story about a tiny red train car that she used to read to her children when they were toddlers. It was an obvious relief to Rebecca as she slumped into Miguel (Jon Huertas) with exhaustion after she finally remembered the word, but the heartbreaking truth was that it took such a toll on her to get there. While the Rebecca we know and love remains, the episode set up how grueling and devastating watching Rebecca lose her grip on the memories that have brought this family so far is going to be. The word caboose seems like such a small thing, but as Rebecca said in Season 5, it's the memories of dancing with Jack (Milo Ventimiglia) in their kitchen, helping the triplets with their homework, and a million other small moments that she's terrified of forgetting. 

No other big mysteries were set up in the premiere as This Is Us already has so many loose threads that still need to be tied up in its final episodes. Fans are still waiting to see which of the Big 3 will take on the primary role of caring for Rebecca as her memory gets worse. Kate (Chrissy Metz) and Toby's (Chris Sullivan) relationship is already on the downturn, but the final season will reveal how it all completely falls apart. Kevin (Justin Hartley) reached another crossroads in his career in the premiere episode and will have to decide perhaps once and for all if his artistic integrity is more important than being a consistent presence in his young children's lives. And none of those tap into filling in more of the blanks in the future timeline at Rebecca's deathbed. 

However, next week Rebecca and Miguel will help Nicky (Griffin Dunne) track down the lost love of his life in the second episode of This Is Us Season 6. If Nicky is able to reunite with his long-lost Sally, we may start to get answers about why he was the one at Rebecca's side in the future timeline instead of Miguel. In short, the This Is Us Season 6 premiere delivered all the emotions we are used to, but we still have so many things to look forward to as the final Pearson chapter unfolds. 

This Is Us continues Tuesdays at 9/8c on NBC.