Mandy Moore and Chrissy Metz Tease 'Even Darker' Moments on 'This Is Us' (Exclusive)

"I think slightly darker, more turbulent times for the family are sort of waiting right around the corner," Moore told ET.

The Pearsons are about to fall on even tougher times, according to the women in the family.

ET caught up with both Chrissy Metz and Mandy Moore, who portray Kate and Rebecca Pearson on This Is Us, following Tuesday's intense episode, and got some clues as to what viewers can expect in the coming weeks.

On this week's This Is Us, Kevin Pearson (Justin Hartley) dumps Sophie (Alexandra Breckenridge) as he continues to battle an addiction to pain pills. Meanwhile, Randall Pearson (Sterling K. Brown) and his wife, Beth (Susan Kelechi Watson), struggle to figure out what is best for their foster child whose mother is behind bars. 

The only lighter moment in the episode comes from Kate, who is celebrating being pregnant, and determining whether she wants to just go ahead and marry Toby (Chris Sullivan) at the courthouse.

"We've never ever gone down [this road]," Metz told ET's Carly Steel at the SAG-AFTRA Foundation Patron of the Artists Awards 2017 on Thursday night of the upcoming episodes. "I mean, literally, we're calling it the trilogy. So, it's sort of Kate, Kevin and Randall-centric. ...It's so beautifully done and the performances are... I cant even explain it. I know I always say that, but there's so much gonna be happening!"

As for Kate's baby news, the 37-year-old actress mused, "I think it's kind of interesting that they, you know, are having a child out of wedlock. They've only been together a year, but they really genuinely love each other -- and it feels right for them. ...Not everybody's story is the same and I think it's bringing some sort of understanding that we all have different lives and it's OK to do things unconventionally."

ET's Lauren Zima also spoke with Moore at a Friendsgiving event presented by American Express about the upcoming episodes of This Is Us and she revealed that the storylines are going to become "slightly darker."

"I think slightly darker, more turbulent times for the family are sort of waiting right around the corner," she dished. "And nothing necessarily that has to do with Jack [Pearson]’s passing."

Moore also talked about the next episodes being a trilogy. "The first episode is about Kevin, the second is about Kate and the third is about Randall and they’re very much interconnected, especially their stories in the past," she noted. "They sort of [tell] the same story from different points of view. It’s beautiful, but I encourage people to be patient because it’s ...you’re going to see some of your favorite characters in a more unfavorable light."

The 33-year-old actress quickly added, "It’s for a reason and we’re going to work our way to redemption."

This Is Us airs Tuesday nights on NBC.

While Kevin didn't end up getting engaged on this week's episode, Hartley did tie the knot in real life, and spilled the wedding details to ET! 

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