'This Is Us': 8 Biggest Questions After the Season 4 Fall Finale

Who is Kevin's [SPOILER]? What happened to Randall? How is Rebecca faring? ET breaks down the mysteries we want solved in 2020.

Warning: Spoiler alert! Do not proceed if you have not watched Tuesday's season four fall finale of This Is Us.

We have some very big questions.

On Tuesday's season four fall finale of This Is Us, titled "So Long, Marianne," the Pearsons' annual Thanksgiving dinner was meant to be a celebratory feast with new friends and family members, but turned into a grim foreshadowing of what was to come for the clan nine months later. Rebecca's deteriorating health had been an underlying focus for much of the season, but the gravity of her memory loss was so serious that even she noticed something was very, very wrong. 

While we were supposed to believe that after Rebecca left Randall's Pennsylvania home on Thanksgiving, she detoured to a nearby playground before going to the grocery store and later eating alone at a Chinese restaurant (the only establishments often open on that particular holiday), it wasn't the case at all. That Rebecca's lengthy jaunt away wasn't on Thanksgiving 2019, but on Kevin, Kate and Randall's 40th birthday in the summer of 2020. As the episode revealed, a lot had changed in the nine months in between -- and Rebecca's memory had aggressively disintegrated.

But Rebecca's slow spiral down wasn't the only notable revelation from Tuesday's episode. Following the final hour of 2019, ET breaks down the eight biggest questions we have when This Is Us returns in January.  

1. What happened to Rebecca during the nine months in between Thanksgiving dinner and the 40th birthday party? This Is Us pulled a signature misdirect in the episode, lead us to believe that after Rebecca left Randall's home in Philadelphia on Thanksgiving Day, she made her way to the playground (where she hallucinated a young William), went to the grocery store to buy flowers (instead of pie), forgot her phone at the checkout line and then had a meal at a nearby Chinese restaurant. Well, Rebecca did leave Randall's home to get some air -- only she didn't go to any of those places. Instead, all of these moments happened nine months later on the Big Three's 40th birthday.

While we got closure on Rebecca's whereabouts that Thanksgiving afternoon -- she went to the movies before going to the store to get pie and returning home -- it was just the start of her coming to the terms with the fact that her memory is starting to deteriorate. She confessed to Randall away from the Thanksgiving festivities, "I was halfway through the trailer of Cats and I couldn't remember what movie I went to go see. I think I need to see a doctor." What's clear is that Rebecca's condition has dramatically worsened since Thanksgiving up until the birthday party. What's unclear is if she's been medically diagnosed by a doctor and what the condition is. No matter, it's apparent that when Aug. 31, 2020 rolls around, everyone who is around her -- Kevin, Kate and Miguel especially -- are deeply worried about the matriarch's state of mind. 


2. Who is Kevin's pregnant fiancee? One of the biggest bombshells came when Kevin prophesied his own fate. On his 40th birthday, he nonchalantly revealed that his fiancee was "laying down" in the back, trying to recover from a bout of morning sickness, which she's been experiencing "at all hours of the day." Nine months earlier, he proposed to Randall his grandiose life plan of starting his own family after Nicky told Kevin to go back to his life in Los Angeles and Cassidy left to reunite with her own family. "By the time I'm 40 I'm going to have a wife, I'm going to have a kid, the whole shebang." Looks like he definitely aced that goal.

So, who is the mystery woman Kevin is about to marry and is expecting a child with? And is she someone we've already met? When did they meet? A popular season four theory was that Cassidy, Kevin's Alcoholics Anonymous friend-turned-maybe love interest, was the mother to Kevin's mini-me who we briefly met in the future flash-forward. Though it appeared that This Is Us nipped that theory in the bud after having Cassidy return to her husband and son, we wouldn't be surprised if she came back into Kevin's life in the months after Thanksgiving. Or maybe it's Sophie, Kevin's ex-wife he married too young? Or maybe it's Beth's cousin, Zoe? Or, she could be someone we haven't even met yet. Is this mystery woman The One for Kevin? Judging by everything he's gone through, we're really hoping that's the case.

3. Why are Randall and Kevin no longer speaking? The brothers have had a rocky go of it over the course of the series, and when their 40th birthday rolls around, Randall and Kevin aren't even talking. Kevin breaks the news to a memory-logged Rebecca, who asks him when Randall is arriving, the answer to a question she's forgotten many times before based on Kevin's annoyed reaction. "We're not speaking, remember?" he reminded her. What happened in the nine-month time span? At Thanksgiving, the siblings were as close as they ever were, with Kevin even opening up about his wishes for his personal life. So, what the heck happened? 

One potential theory we have, though completely unfounded, is that their stalemate could be Rebecca-related. It is notable that Randall is the one Rebecca divulged all her vulnerabilities to regarding her diminishing memory. But wouldn't that be the obvious answer? We're not 100 percent sold on the fact that it's Rebecca who is the main factor playing into Randall and Kevin's new feud. It is entirely believable that Randall and Rebecca could have kept her memory loss to themselves, and Kevin could have accidentally found out. But maybe it could be related to Kevin's new woman? What happened that was so major that caused such an irreparable fracture between the two brothers? 


4. Are Kate and Toby broken up? The couple hasn't been on solid footing for a while, what with their bickering over every possible little thing and them keeping secrets from each other. But it all seemingly comes to a head when Kate unexpectedly discovers Toby's group text with his Crossfit workout pals, with one damning text exchange that you just can't delete. While Kate's name is never mentioned in the exchange, it doesn't take a rocket scientist to put two and two together. "Trying to get past it, but it's hard," Toby's text read, followed by a reply from a nameless woman going by "LadyKryptonite5," "Don't let her bring you down. Here for you." 

Now, we may be reading a little too much into this but that doesn't sound promising. If your husband is venting to strangers about your marital problems, it's just a matter of time before everything comes to blows. It all tracks that Kate and Toby could be separated by the time the Big Three's 40th birthday arrives, as Toby's absence is notable. And we can't forget his solo arrival in the future flash-forward in the season three finale. Is "LadyKryptonite5" more than just a friendly Crossfit workout partner, too? Why is Toby hiding the identity of this woman on his phone?

5. Is Nicky still sober? When Nicky tells Kevin to go back to living the actor life in sunny California, promising that he'll be fine on his own, we had to wonder: Has he become Kevin's surrogate father figure? Will he stay true to his sobriety without Kevin by his side pushing him? We've come to really enjoy their unusual dynamic; they're the yin to the other's yang. 

6. Will Tess get her first girlfriend? It took a while to reach this point for the character, but Tess decided to come out to her friends and classmates the only way millennials know how: through Instagram. After posting a photo of Zendaya as her celebrity crush, Tess was surprised to find support, love and words of encouragement from her fellow peers. Now that she's comfortably out, will we see her start to date and maybe even get her first girlfriend?


7. Will we ever find out how Deja's birth mom feels about her dating Malik? It was nice to see Deja's birth mom settled into a stable job and find her place in the world after a roller-coaster run that forced her to give up Deja to Randall and Beth. What was curious was the lack of conversation between Deja and her birth mother about her dating a single teenage dad. Is she aware that Deja is seeing Malik? What does she really think about the whole thing? What is Beth to Deja? 

8. Will we revisit the 40th birthday party in the second half of the season? While there's the future flash-forward to Rebecca's end days, the fall finale introduced another pivotal guidepost for the Pearson family with Kevin, Kate and Randall's 40th birthday. While each season of This Is Us typically opens with an episode celebrating another year around the sun for the Big Three, it's significant that we're getting a glimpse into that day half a season early. So, is the series abandoning its yearly tradition by doing this? Will we get more answers to the state of the Pearson family on Aug. 31, 2020 before season five? Time will tell.

This Is Us returns Tuesday, Jan. 14 at 9 p.m. ET/PT on NBC.

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