Everything You Need to Know About Tuesday's New 'This Is Us'

A 'bumpy' time in Vegas

Lighter does not always mean easier however, as Aptaker describes Kate and Toby's bachelor/bachelorette parties as "bumpy," given the mix of friends and family that the couples brings with them to the city.

"What's interesting about Kate and Toby is, if you think back, they don't have huge, deep pools of friends to draw from," Aptaker said. "They stay in with their dog in their cozy apartment. So that means when it's time to assemble their groups of people for their bachelor and bachelorette parties, it's not necessarily this perfect cohesive group of friends; it's a bit more of a motley crew... Everyone heads to Vegas with somewhat disastrous results."

Madison and Beth collide

Aptaker teases Kate's new friend Madison (Caitlin Thompson) and Randall's wife and fan-favorite Beth (Susan Kelechi Watson) as a "little bit of oil and water" situation, which should come with some tension.

Kate and Beth share a moment

"Vegas, Baby" will mark the first time Kate and Beth share significant screen time during the show's history, which Aptaker says is indicative of their distant relationship.

"For Kate to bring Beth into this group that she's already a little stressed about, it's just an added layer of anxiety for her because they don't have a particularly close relationship. But they get to a really unexpected place in the episode."

Toby bonds with Randall and Kevin

Aptaker teases that Toby is looking forward to spending time with Randall (Sterling K. Brown) and Kevin (Justin Hartley) during the bachelor party, looking to forge a bond between his soon-to-be new family.

"It's not smooth sailing," Aptaker said.

Kevin struggles with his recovery

Kevin recently went through rehab for his drug problem after a DUI, and being in Las Vegas with his family will definitely prove challenging for the member of The Big Three.

"Vegas is pretty high up there on the list of places that you don't want to go if you're a newly sober guy," Aptaker adds. "He's really, really tested, and we learn that he's been a big Vegas guy. It's one of his favorite places, and he's now going there with a totally different outlook in the world, and it's really going to challenge him."

Jack and Rebecca's First Anniversary

Rebecca Pearson (Mandy Moore) may not have been invited to celebrate in Vegas. But in the past, viewers will see her and Jackie celebrate their anniversary.

The first one in a bowling date Jack plans for the love of his life.

"This story is a charm offensive," Aptaker said. "As we know, Jack is the big romantic; he always overshadows Rebecca a little bit. She'll give him a gift, and then he'll give her the world and blow her away."

The Big Three step up in the 90's

For their anniversary in the 90's era, viewers will see Jack and Rebecca saying they're too exhausted to have a big celebration for their anniversary. But the kids have a different idea.

"They step in to throw an awesome party for their parents, not realizing that when you're a 10-year-old throwing a party, you're actually making more work for the people you want to celebrate as opposed to giving them a nice night off," Aptaker reveals.

A "Bittersweet" Moment

Moore revealed that seeing the loving couple directly after the back-to-back episodes dealing with Jack's death felt "bittersweet," but Aptaker said having the anniversary storyline right after those moments allows fans to dive into a happier part of the Pearson's history.

"Knowing what we now know, there's always going to be a little bit of that," he said. "But our hope — and why we wanted to come back with one that was really fun and romantic and celebratory — is that people can still watch the show and see his life was too short but he had this amazing, full life with all these really great moments."

"We hope the audience can enjoy losing themselves in the happier times in this family and forget a little bit what does wind up happening to him and just revel in how great they were when they were," he added.

This Is Us airs Tuesdays at 9 p.m. ET on NBC.