This Is Us star Mandy Moore on portraying Rebecca's dementia, season 5, and flash-forward hints

Dan Snierson
·9 min read

NBC

During a particularly intense stretch of the season 4 finale of This Is Us, a child's birthday party devolved into a childish, charged fight between the Pearson brothers. The cause of Kevin's clash with Randall was rooted in decades of sibling rivalry, but the catalyst was their differing opinions on the care for their mother, Rebecca (Mandy Moore), who is in the early stages of Alzheimer's. As you remember, Rebecca declined to participate in an experimental study at a St. Louis university — a decision that Kevin (Justin Hartley) supported — but Randall (Sterling K. Brown) guilt-tripped her into changing her mind. And when Kevin discovered that Randall was responsible for her sudden change of heart… well, the family fireworks began. As season 5 of NBC's hit family drama begins, it's time to sweep up the ashes of the brothers' relationship and see what might be able to rise from them.

Like Milo Ventimiglia, who plays her onscreen late husband, Jack, Moore felt a rush of protective parental emotion when she first learned about the brutal words "that were designed to make maximum impact and push every button and every bruise inside" during the finale's nauseating showdown. "I was not there for that particular scene, but I would have stopped that fight," says Moore, who spoke to EW as part of a 92nd Street Y virtual conversation this summer. "I would have broken it up. I don't want to see my children come to blows like that. No mother wants to."

That ferocious finale capped a season in which Rebecca started to come to terms with her mild cognitive impairment and weighed treatment options. In preparation for this ambitious arc that will follow her through the end of the show, the This Is Us team sought out expertise and advice from medical professionals, and a neurologist was on set for the episode in which Rebecca was administered diagnostic tests. Moore embarked on her own journey of discovery to tackle this daunting part of Rebecca's story, immersing herself in all sorts of research. "I somehow haven't had a personal connection to Alzheimer's or dementia, so I was very nervous about making sure that I handled this correctly and responsibly, and I wanted to do all the research possible," says Moore. "So I really dove in pretty deep. I listened to podcasts, I watched documentaries, I read books, and I spoke to a couple of neurologists as well, because the details really matter. And we're lucky to have this wide swath of people that watch our show, and I'm sure many people recognize this in their own families. This particular story is a mirror for them. I wanted to make sure that all the details were correct."

One book proved especially enlightening: On Pluto: Inside the Mind of Alzheimer's, written by journalist Greg O'Brien, who himself was diagnosed with the disease in 2009 and reported on his experience. "[O'Brien] has written all kinds of incredible firsthand accounts of what it's like to grapple with this disease," Moore says. "I carried his book around as sort of a de facto bible while we were shooting a lot of [season 4], because it gave such a rich, illustrative point of reference as to what someone's going through in such a dynamic way that I don't think I was able to get just from reading research papers."

Of course, no amount of research can override the emotions that bubble up around managing such a cruel and debilitating disease. Although Randall researched treatments and scored a spot for his mother into an experimental study at Washington University in St. Louis, she declined to participate so she could spend more time with her family in Los Angeles. The scene in which Rebecca revealed her decision was incredibly challenging to pull off. "This sense of authority that she has when she tells Randall, 'I'm not going to do that clinical trial, I've made this choice for myself. When I picture the next few years of my life, I don't know what it looks like necessarily, but I know that I want to be surrounded by my family,' is really bold and brave," says Moore. "And I feel like it's a color we haven't necessarily seen of Rebecca, especially at this phase of her life."

Randall did not take no for an answer, and the fact that he strong-armed her into a yes rankled Kevin as well as fans. Swept in the fear of possibly losing another parent, the dutiful son seemed to move from fiercely advocating for the health of his mother to crossing a line and not respecting her wishes. "I can absolutely understand a son who lost his biological father, his adopted father, and now has the opportunity to do whatever it takes to care for his mom," says Moore. "I don't know if I necessarily agree with the means by which he got Rebecca to agree to this. But I could also understand, this is a woman who is fully understanding of the resources that are out there and has made this decision with a lot of information at her fingertips that instead of pressing forward and being a part of some sort of clinical trial or really doing anything that feels like too much, she really wants to spend this time with her family. And the last two seasons, we've really seen so much repair with her children, and this season included, that I think she really wants to enjoy the fruits of her labor of finally getting on the same page with Kate [Chrissy Metz] and with Kevin. Things have always been pretty great with Randall, but now that she lives in California and she has her grandchild there and potentially more grandchildren in the future, I think she really didn't take this decision lightly. So it'll be interesting to see how it unfolds in season 5."

What might life look like for Rebecca in St. Louis if she still does participate in the study, with Miguel (Jon Huertas) dutifully at her side? The real-world pandemic — which will be reflected on the show — will "dictate a lot" in terms of how this story will be told, she says. That said: "In my mind, the world of St. Louis is a transformative one, hopefully for Rebecca… Somehow she ends up back at the cabin celebrating Kevin and Kate's and Randall and Jack's birthday, and has that episode where she's a bit out of sorts. So whether or not the clinical trial is working, or whether this is just a normal step back for someone who's in the beginning of a battle with dementia or Alzheimer's, remains to be seen." (Moore supports creator Dan Fogelman's decision to incorporate both COVID-19 and the Black Lives Matter movement into season 5's stories. "We're all united in our belief that it's important to address what's happening in the world in a sensitive fashion, in a realistic fashion," she says. "I think our show has just always been true to reflecting the world.")

For some time, viewers have been promised a deeper examination of Rebecca and Miguel's relationship, specifically why these two cut off communication post-Jack's death, and how they wound up reconnecting. Are these matters finally illuminated in season 5? "I've been told yes, but I also was told last year, so who knows?" Moore says with a laugh. "I'm guessing it has to be this season, because season 6 [has] 18 episodes to wrap up this whole story. Hopefully that will be simultaneously shown with what their life looks like now, and how Miguel was a shoulder for her to lean on in the weeks and months and years after Jack passed away. Obviously [he] is her caregiver now that she's suffering from dementia. That would be an interesting parallel to see that he's been this rock in her life the whole time."

But was Miguel there at the end of her life? In the deep-future flash-forward scenes at Kevin's house, it was Uncle Nicky (Griffin Dunne) and not Miguel who was seen at the bedside of a gravely ailing Rebecca. What other surprises await viewers as they are gradually shown more of that day? "In typical This Is Us fashion, there are going to be things that are shocking, and some surprises that aren't as much of a surprise to people," Moore says. "Obviously there's an intention of revealing things slowly and peeling back the layers of the onion, but I know there's never an intention to misdirect people. It's just like: Have you really been paying attention? Or: You just don't know the fuller picture yet. We're just super-zoomed-in and looking at something on a micro level. And as we start to look at the macro picture of things, things get revealed. There's a couple of things that I think people are going to be like, "Oh! Oh — oh. I didn't see that coming."

Do these revelations cover a range of emotions? "They definitely run the gamut," she says. "It's not just [imitates sad trombone] Debbie Downer by any means. It's just like, 'Oh! Oh, okay. That makes sense.' There are bittersweet things, there are some beautiful things, there are some heartbreaking things, but all of it will make sense in the pastiche of this family and this time in their lives."

That scene is a key part of the show's endgame, and like Ventimiglia, Moore relishes those moments in which Fogelman reveals another piece of the puzzle to the cast. "He is an excited kid, talking a million miles a minute about a bunch of ideas that they just came up with in the writers' room or things that they're fleshing out," she says. "I'm trying to remember everything, so then I can come home and tell my husband! But I can never remember everything! I'm like, "Taylor! Oh crap, what did he say? Oh, I can't remember the specifics!" I have a terrible memory when it comes to that stuff."

And when it comes to next week's season 5 premiere — which takes place on the Big Three's 40th birthday and very first birthday — she uses the word "spectacular" to describe what it is to unfold. She also hints that viewers should brace for another TIU trademark moment of whoa. "It's a part of this family's story that I had just never thought about before," she says. "Because you maybe feel like, 'Oh, what's the story? There is no story there.' But there's a story there."

The Pearson story resumes on Oct. 27 at 9 p.m. on NBC. Metz also dropped hints about the new season, as did Chris Sullivan. And you might want to hear what Ventimiglia had to say. Susan Kelechi Watson, too. Oh, and Sterling K. Brown.

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