'This Is Us' fall finale reveals shocking Nicky bombshell

Warning: Major spoilers ahead from Tuesday's fall finale of "This Is Us". Beware, you have been warned.

"This Is Us" pulled a fast one on all of us.

We presumed that Jack's younger brother, Nicky (Michael Angarano), perished in the Vietnam War -- mainly because that was what the show led us to believe -- and that his death, as a casualty of war, was one of the reasons Jack (Milo Ventimiglia) kept quiet about his wartime experience to his family and to his friends. In the closing moments of Tuesday's fall finale, circuitously titled, "The Beginning of the End is the Beginning," we now know that we were very, very wrong about what happened to Nicky.

Nicky didn't actually die in the Vietnam War as we thought, he's still alive.

Years after the war (at least, that's what we're assuming), we see a grizzly bespectacled man looking eerily similar to Nicky enter a modest-sized home. You'd think nothing of it until the camera zooms in and we see letters addressed to a Nicholas Pearson, who is residing in the small town of Bradford, Pennsylvania.

Mind. Blown.

How did he end up in Bradford, Pennsylvania? And is that really Nicky? Before we speculate, here's how the shocking reveal came about: During the war, Jack discovers Nicky is high off prescription pills belonging to another army mate. Disappointed, worried and protective of his younger sibling, Jack vows he's going to get him "clean again," a declaration Nicky is not interested in following through on. "I don't want to get clean, Jack," Nicky snarls, telling him he's not going to complete the mission. "I see it all again when I'm clean."

With their two-week stay together in its final days, Jack goes looking for Nicky after he disappears. When they suddenly hear a loud explosion in the water, things get worse. Right at that moment, one of his army pals yells out that "one of our guys was on it!" leading Jack (and us) to believe that person was the ill-fated Nicky. While we don't actually know the aftermath of the boat explosion or who was on it (if it wasn't Nicky) and what happened to them, we move to the present day, where Kevin (Justin Hartley) learns from the local Vietnamese guide who's been helping him and Zoe (Melanie Liburd) that his uncle didn't actually die during the war.

"I was going to suggest something you could bring home from here, perhaps something you could lay for your war memorial for your uncle one day but I must have misheard because none of your family died in the war," the local guide nonchalantly tells Kevin, whose ears immediately perk up. Ours too. "I went to a database for the war memorial," the guide explains. "Nicholas Pearson, 46th Infantry, his name's not there. He might be dead but he didn't die in Vietnam -- not in the war anyway."

Cue the aforementioned Nicky scene, where we presumably meet older Nicky as he checks his mail and shrugs off his coat in his Pennsylvania home. This twist, which we didn't think was even possible, changes literally everything.

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"It’s a big story. It’s surprising. It’s fair to say that clearly, something broke in Vietnam for Jack as it relates to his brother, and I think people will be satisfied with what we’re doing there even if they don’t always like it," creator Dan Fogelman told ET in October following the "Vietnam" episode. "It takes place in a compressed period of time that was a defining period of time for Jack as it relates to his brother. I think it would be borderline impossible to guess where it’s going because it’s very specific.”

“It’s comparable to some of our biggest stuff in that it’s going to feel really massive, in terms of what it does to Jack," he hinted at the time. "Jack buried a portion of his life when he came back from the war. What we’re going to explore this season is what he buried.”

There were several clues hinting to the possibility that Nicky may still be alive, a theory we posted last October after the season two episode, "Brothers," where we first became aware of the existence of Jack's younger brother. When the Nicky bombshell dropped, we couldn't help but go back to the episode last season where Jack and teen Randall (Niles Fitch) visit the Vietnam War Memorial in Washington, D.C.

In that episode, Jack noticeably gets emotional during one particular spot on the wall and maybe we were wrong to assume it was Nicky's name he saw. Could it have been the kid, Squirrel (Moses Storm), who died after stepping on the landmine? Considering that Nicky is living and breathing, that very well could have been it. And remember in "Moonshadow," when Mrs. Peabody (Debra Mooney) commented that Jack came back from the war relatively "normal," was she subtly comparing him to Nicky?

Shockingly, the Nicky twist isn't the only mystery the fall finale addressed. Here are our biggest questions regarding every other non-Nicky-related reveal:

1. Seriously, who is "her"? The season-long "her" mystery continues, but we can strike one person off the list: Beth (Susan Kelechi Watson). In a scene set in the future that seemed tailor-made to put to bed any "Beth is 'her'!" theories, adult Tess (Iantha Richardson) tells pops that she'll call her mom in the car. Later, Beth says they're all "going to see Randall's mother." First thought brings you to Rebecca (Mandy Moore), but she could also be referring to Randall's birth mother, Laurel, who we presumed to have died in childbirth, per William. At least we know it's not Beth.

2. How does Tess handle her sexuality? One of the highlights was Tess' (Eris Baker) raw, heartfelt coming-out speech to her parents in the kitchen. Because it's such an important moment for Tess and the show, we're choosing to include their entire exchange here:

Tess: "I'm sorry I've been so weird lately. I feel uncomfortable around you guys all of a sudden. I have a stomach ache all the time. I don't want to keep secrets... Um, people at school have been having crushes of stuff and lots of girls have boyfriends but I don't want one. It's because I think I might like girls, not boys. I don't know, maybe I don't. I didn't want to tell you guys because I didn't want it to become a thing."
Randall: "We're your parents, we're here to help you in a very cool, laid-back kind of way without it becoming a thing."
Beth: "We love you, no matter what, okay? You see me? Look at your dad, you see him? Do you see anything other than two people who love you more than any two people could love anyone in the entire world?"
Tess, a smile creeping up on her face and letting out a sigh of relief: "Okay, thanks... I don't really want to talk about it anymore... Not right now, anyway."

We're hoping that the show doesn't gloss over Tess' journey of self-discovery like it has done so in the weeks following Zoe's meaningful confession two episodes ago about why she can't have substantive, intimate relationships with men (she was sexually abused by her father). (We're still waiting, "This Is Us" writers!) And we're so thankful that the conversation Tess, Randall (Sterling K. Brown) and Beth had was real, loving and rid of every ounce of judgment.

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3. Are Randall and Beth, gasp, separated? Maybe we're reading too much into Beth's reaction after she finds out from her colleague that Randall and Tess are on their way to her, but it seemed quite nonchalant, didn't it? As we saw years earlier, Randall went against Beth's wishes and declared he was going to continue on with the campaign. Even though he was told by his campaign manager that his poll numbers are low. Did that schism become bigger and bigger as the years went on?

4. Will we see Kate give birth to her baby boy? We learn that Kate (Chrissy Metz) and Toby (Chris Sullivan) are expecting a boy and that Kate is going back to school so she can get that college degree. Still, there is a lot that can go wrong before her due date.

5. But. How. Is. Nicky. Still. Alive?! We're going to be thinking about this one for a while. The only plausible -- and not cuckoo-crazy -- theory is that Nicky's death was faked in order for him to escape the trials of war. (After all, Jack had Nicky's dog tags in the box of Vietnam War mementos.) If we're going down that road, then could Jack have planned the boat explosion with Nicky on it, taking him away to a remote place no one would think to turn to and thusly enacting a fail-safe plan for his brother to leave Vietnam unscathed? If that turns out to be the case, we need to know how he pulled this off. Another possible theory could be Jack thought his brother died in the war after he went missing (Jack found Nicky's ditched dog tags somewhere), and thus, told everyone. But if his death was faked, why didn't Nicky change his name? Yup, we sure have some questions about this twist...

6. Are we midway through This Is Us canon? If I were a betting woman, I'd say yes. There's a line thrown in this episode where a minor character suggests we're "only midway through the story." Is that Fogelman being cute and letting us know there's a five-season plan? I'm choosing to believe so, especially since parts of the series finale have already been filmed.

"This Is Us" returns in 2019 on NBC.

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