It wouldn't be This Is Us without soul-crushing twists, and tonight's season finale will likely pack a punch.
The sophomore finale, simply titled "The Wedding," takes place at Kate and Toby's nuptials, with members of the Pearson clan gathering together to see the couple down the aisle. And somehow, Jack -- who died in 1998 -- makes an appearance at the wedding ceremony looking much older than we're used to. Ever since the trailer was released last week, fans have theorized and hypothesized possible explanations for Jack's "surprise" return, with some of the more outrageous theories ranging from Jack faking his own death to it actually being Jack's presumed dead younger brother, Nicky.
"You will know why I am in aged Jack makeup," Milo Ventimiglia told ET's Leanne Aguilera on Monday at the South by Southwest finale presentation in Austin, Texas. "I don't want to tease anything other than you've seen the photos. Just be excited and enjoy."
So what lies ahead for the Pearsons on Tuesday's anticipated season finale? ET scoured the Internet to highlight the five most intriguing theories that may explain why Jack is an old man, and if we should be worried about the fates of other beloved members of the family.
1. Rebecca dies.
This Is Us fans have spent the season coming to terms with Jack’s death and are now waiting for the next shoe to drop. Theories have been swirling that the Pearson clan is about to deal with another major loss in the family, and Rebecca and Beth seem to be the most popular targets of these devastating theories. There could even be a plausible reason to think Deja or Deja's mom, Shauna, may be in danger. (The last episode didn't shy away from the presence of the gun Shauna's boyfriend kept close by.)
“Geez, guys! Wow, why are you trying to kill everybody off?” Mandy Moore exclaimed to ET at the show’s SXSW finale presentation, claiming she hadn’t heard any rumors. “That would be news to me. I’m gonna say probably no to that, but who knows? I’m just unaware perhaps.”
Ventimiglia, however, was much less reassuring: “I expect that over the course of the show there may be more deaths than just Jack and William, but we'll see. We'll see what happens.”
While another death or terminal disease would be devastating, the morbid truth remains that it would make a lot of sense for Rebecca to see Jack’s welcoming face if she were to succumb to some kind of illness (and remember, she had that cancer scare all those years ago). It would also contextualize Jack's potentially telling words to Rebecca, when he says, "Where'd the time go, Bec?"
2. Kate envisions what her wedding day would be like with Jack there.
While the finale preview seems to show Jack speaking to Rebecca, what if the whole moment is a figment of Kate’s imagination? The father-daughter duo have one of the strongest connections in the Pearson family, so it wouldn’t be a surprise if Kate was so desperate to have her dad present on her big day that she imagined, just for a moment, that he was.
It certainly would make sense for an older Jack to appear in Kate's visions, as she's the last member of the grown-up Big Three to share a moment with papa Pearson. Back in November, Chrissy Metz told ET that she and the writers "talk about it" a lot. "I have my dream idea," she said at the time. It certainly would make sense for that dream idea to be wedding-related, wouldn't it?
3. Jack didn't actually die.
Bear with us. We know we’ve seen Jack’s body lying in the hospital -- well, a blurry image from afar of Jack's body. We know Rebecca was there right after the doctors tried -- and failed -- to save his life. But what it? WHAT IF?
Some of the most out-there conspiracy theories posit that Jack faked his death, possibly to return to the solitude he sought when trying to get sober earlier this season. But there’s just no way he could stay away for Kate’s wedding. (There’s gotta be a chance!)
4. That's really Nicky, Jack's younger brother.
OK, stay with us. It's a bit of a stretch, but one theory floating around is the revelation that that's actually not Jack with Rebecca, but his younger brother, Nicky, previously thought to have died in the Vietnam War. One clue that could possibly corroborate this theory, or at least give it some legs -- however nutty it may seem -- is the fact that Jack (or Nicky) is wearing metal-rimmed glasses, a signature identifier that the show established earlier this season as differentiating Jack from Nicky when they were younger.
Are we completely bonkers for going down this route? Maybe. But we're not alone in thinking this could be a shocking reality.
5. It's an alternate universe.
Jack’s still alive somewhere, right? RIGHT?
But seriously, many beloved TV shows have explored the alternate universe theory through “What if?” episodes, where fans get to see how the characters’ lives would have played out under different circumstances. Somewhere, there’s a world where Jack Pearson got to walk his “Bug” down the aisle, and in that world, we just bought stock in Kleenex because we’re about to cry a thousand tears.
The This Is Us season two finale airs Tuesday at 9 p.m. ET/PT on NBC.
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