This Is Us stars and creator explain what it was like to film half the finale years in advance

After an emotionally crushing train trip into the afterlife, the series finale of This Is Us transported viewers to the funeral of Rebecca Pearson, where the Big Three and their extended families paid final respects to their 12-on-a-10-scale matriarch while gazing into the middle distance and pondering next steps in life.

"Us" didn't just live in the realm of the future, though. The episode rolled out the welcome mat on a relaxing day in the early '90s, when Jack (Milo Ventimiglia), Rebecca (Mandy Moore), and their preteen children played silly games like four square and Pin the Tail on the Donkey, watched home movies, and learned to shave. It was all about the little things, or as Jack liked to call them, "the big things."

As series creator Dan Fogelman pondered how to end his multigenerational, multi-feeling family drama with uplift and closure after the beautiful devastation of the penultimate episode, he gravitated toward the warm embrace of the past.

"So much of the narrative about this show has been about these big, surprising twists and the deaths of major beloved characters," he tells EW. "But at the end of the day, what I think really drew people to the show was just the simplicity of family stories and remembering your childhood fondly from your adulthood. I thought: How confident, how cool, and how important it would be to just end on a day with these kids at an age you haven't seen in a while, that was just a simple, regular day in the life? That feels like a day in the life of many families on a lazy Saturday afternoon, as opposed to having to do anything that is super complicated or gigantic."

The story line did indeed whisk viewers back to more innocent times, and you probably noticed that the actors who played the Big Three (Parker Bates as Kevin, Lonnie Chavis as Randall, and Mackenzie Hancsicsak as Kate) looked a little younger than perhaps you remembered them. (Same goes for the early-days-of-the-Big-Three chant scene with Kaz Womack as Kevin, Ca'Ron Jaden Coleman as Randall, and Isabelle Rose Landau.) That's because these scenes weren't filmed in late April and early May with the rest of the finale — they were actually shot three seasons ago. So in essence, your nostalgia was their nostalgia was all our nostalgia.

Why all the advance planning? Fogelman didn't need a degree in biology to realize that if he waited until the final season to film these same kids, they were not only not going to get any younger, they were going to get much older and taller. So he arranged a week of filming in order to bottle a moment and store it away for years, allowing it to ripen for peak nostalgia.

It was a nice leap of faith in the creative process — and on the business end of things as well. "Nobody balked," Fogelman says. "I was like, 'Listen, we're going to make this now. And you're either going to pay for it now or you're going to pay for it later. [Laughs] And they had such trust in us that it was never going to be a situation where we're like, 'Oh, we've changed our mind. We're not going to use any of that.' Because that's where you really would've gotten screwed financially. To the credit of the studio [20th Television] and network [NBC], four or five days of shooting stuff for four years later is not an inexpensive undertaking. They always really trusted us to do our thing."

So did the actors, who were asked to film these scenes with no real context of how they would fit into the endgame years later. "They just never questioned anything," Fogelman says, pointing out that the scenes didn't require any real knowledge of serialized events. "I was like, 'Guys, we're going to go spend the extra four days on set, and you're going to shoot four days' worth of material with the kids that won't air for years and is untethered to anything else you're doing.' And they were like, 'Great!' Then they came in and nailed it every single day. I mean, you would think there would be a lot of questions — outside of anything that they needed to know for their character — they just never balked or complained.

The adult actors in those scenes credit their go-with-the-flow spirit to their devout faith in Fogelman. "I kind of remember it, I kind of don't," Moore says with a laugh. "We were not even halfway through the series. There was so much story left to tell that when this was inserted for a week of filming, you're like, 'Okay…' I remember thinking, 'I'm not sure how this is going to factor in, but cool, it's really beautiful. This is such a neat, quiet scene in bed with Milo about the scar above my eye.' I mean, just all these little simple details — we're so used to doing bits and pieces of montages on the show that so much of it felt like that — just slightly elongated versions of bits and pieces we would shoot for montages. So I just trusted. I was like, 'Eh, Dan has a master plan. He's never gotten it wrong before, so I'm sure he knows what he's doing.'"

"We were just understanding that we're going to be shooting something that we may not be able to get in the future," Ventimiglia recalls. "Dan had an idea about filming a particular moment in time with the kids before they grew up. It didn't matter if it was going to end up in the final edit or not. Dan has created an environment that it didn't matter what he was putting in front of us, everybody was 100 percent committed to it. Everybody was there, wanting to be a part of whatever it was that he was presenting to us."

Aside from a little extra secrecy with the script, it was a rather quotidian week of filming. "That was the beginning of season 3, and we went through all of season 3, which for me was all the Vietnam story line," Ventimiglia says. "We had so much work still to do. It didn't seem that big. It didn't seem like one of those things that you think, 'Wow, this is going to be a massive moment for the show. Thank God Dan was thinking ahead to get it!' [They] just played as any other scene[s] that we shot, which was good. It kind of took the pressure off. Maybe some people would feel pressure from knowing that, 'Hey, this isn't gonna see the light of day for four more years, but we're gonna shoot it now.' I remember getting to that scene where we're sitting around with the kids and Mandy sitting on the floor, I'm sitting on the couch, Lonnie's sitting next to me, and Parker and Mackenzie are there. And Ken [Olin, who directed the finale] had this push-in on Mandy and push-in on me, and that just ended the scene. I remember Mandy and I walking off set and Dan going, 'Those were the final shots of the show.' I mean, he said it like it was in stone."

Fogleman insists that he didn't feel pressure about locking in the ending of his series so far in advance. "I knew we had it," he says. "I knew it was good. But ironically, as we were getting deeper on the season, the job was so hard and so much work that the last thing I needed to think about was looking at footage from an episode that doesn't exist yet and isn't going to air forever."

And so the footage sat. And sat. And when it was done sitting, it sat a lot longer. Finally, in the sixth and final season, Fogelman thought: "I should probably go look at that stuff and make sure that the finale's good and that I don't need anything and I don't have to adjust the plan and say, 'Oh, this doesn't all work. I really should make this the third-to-last episode.'"

But he was so busy with the other episodes that he put it off just a little longer. And then, finally, "We hit a point a few months ago where I was like, 'Guys, it's time. I have to look at this,'" he says. "I remember very vividly — it came in my inbox, it said, '618 [season 6, episode 18] Rough Assembly.' And it was half, if not more, of the episode — the final episode of series — shot years ago. I had it on my laptop and I shared it to the big screen downstairs. And I said to my wife [Caitlin Thompson, who plays Madison], 'Do you want to watch the finale with me before I've seen anything?' Which I never do with anyone, but I was almost too nauseous to look at it by myself. But we sat and we watched it and we were just so absorbed. And it was such a nice experience. I was just very excited by it."

The stars felt a similar rush reading the finale script and seeing that vintage footage. That included a stirring hallway scene featuring Randall (Sterling K. Brown) and William (Ron Cephas Jones) that Jones remembers being filmed during the making of one the show's most beloved episodes, season 1's "Memphis." That wondrous weeper sent Randall and William on a joyous trip to William's birth city so father could show son his roots, but alas, it ended with the terminally ill William passing away in the hospital. "Us" revisited that morning when the pair were about to leave on the trip: William kissed little Tess (Eris Baker) and Annie (Faithe) goodbye before he marveled at the idea of his being a grandfather, and how little he knew his own. (It was heartbreaking that the kids — and Randall — wouldn't have William around for much longer, but his name would live on, with Deja telling Randall decades later that she was going to call her son William.)

"Dan called me and said, 'Do you remember that scene that we cut? I found the place for it in the finale,'" Jones recalls. "To be honest with you, I didn't know how it was going to fit or where they were going to use it. I vaguely remembered it, but I didn't remember the specificity of it. So that was more like, 'Ooh, I'm really glad I get a chance at least be seen in the last episode!' [Laughs] Then when I saw it, it was like, 'Whoa, I forgot how beautiful it was when he was reflecting on being a grandfather — and how in retrospect it was attached to everything.' You hear that speech and you go, 'Everything is attached to something else, whether it be in the future or in the past'… The genius of Dan Fogelman is that he's able to have these pieces where when they shoot it, it may not fit, and he doesn't throw it away. He'll put it on the shelf. Sometimes [he'll] go back and say, 'Remember that scene we shot where we took that out? This will be a perfect time to place that piece into this tapestry.' That's what happened with that scene."

What resonated with Jones was the further contextualization of the weight of what was to come, paired with the depth of what had happened in his too-brief time with the Pearsons. "There was a cloud around William's heart," the actor says. "William knew in his heart that he probably wasn't going to be coming back. And you could see it when you look at the scene, when he says, 'Man, a grandfather?' He actually got an opportunity not only to be a father, but to experience being a grandfather. This was something that he never dreamed that he would ever get again — until Randall knocked on his door."

Brown compares Fogelman's work in "Us" to a bit of Boyhood, Richard Linklater's 2013 coming-of-age movie that was filmed over the course of 12 years. "Tears just come streaming down your eyes, man," he says. "No. 1, first of all, it all fits together really, really beautifully. No. 2 was that he saw it. He had it. He really, really had it. He wasn't just talking about having it. Like, he really had it figured out. I was like, 'How do you —?' I stand in awe."

Indeed, all that advance planning paid off — which is probably a good thing, because Fogelman says he had no real backup scenario. There was one filmed sequence, however, that didn't make the final cut: First you see Jack making pancakes for his family, and then adult Randall making pancakes for his family. Randall's family is laughing it up at the breakfast table with William, and when the camera pans away from him and then back in his direction, Deja (Lyric Ross) has replaced William. "It was speaking to the theme that comes at the end of the episode, which is you carry this stuff forward from your childhood into your own family," Fogelman says. "It was really lovely, but it was a little untethered, because we hadn't lived in that time period with Randall and his family. It was really special and beautiful, but it just didn't fit inside of the story line once it was all put together."

Once everything else was all put together, though, "Us" just felt like "a time capsule," Fogelman says. "Especially because the way we shot it, it feels like found footage of a family that you really know, and there's something very nostalgic about it. It's very rewarding and very fulfilling."

And as viewers saw, this trove of footage yielded the show's very last moment of family togetherness, as Randall and Jack exchanged that knowing smile, both of them present in fleeting bliss, savoring those big little things. "I always knew in my mind's eye that the final words of the series would be a simple 'I love you' between two characters — probably Jack and Rebecca — and that the final shot would be some version of the kids or a kid looking at a parent who was looking at his or her family," says Fogelman. "And once I saw that shot of Lonnie looking at Milo, I knew that would be the final shot of the series."

That the past would play such a pivotal role at the end of This Is Us? Well, that might be its most organic and least surprising twist.

Say goodbye to the Pearsons with EW's special This Is Us edition, available to purchase online or wherever magazines are sold.

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