‘This Is Us’ Season 1 Spoilers: Mandy Moore, Chrissy Metz Tease A Heartbreaking Flashback Episode

“This is Us” has been bringing viewers to tears since it premiered in September 2016, and the heartbreak isn’t over yet. The show returned to NBC on an uplifting note in Season 1, episode 11, but stars Mandy Moore and Chrissy Metz say there’s a big blow ahead.

The pair, who play Rebecca and Kate respectively, teased a flashback episode which is sure to leave “This is Us” audiences in shambles. In an interview with Entertainment Tonight, Moore revealed that they’re shooting the episode right now that had her in a frenzy. The actress claimed she was so shocked, she texted “This is Us” creator Dan Fogelman, telling him neither she nor viewers were prepared.

“They’re shooting an episode right now, and I read the script and, like, hyperventilated. I literally had to text Dan, our creator, and was like, ‘People aren’t gonna be ready for this, ‘cause I’m not ready for this,” she shared.

Metz told the publication she could hardly even think about the episode without crying. Moore’s on-screen daughter said she recently sat through a screener of the episode that left her a wreck. Metz added, however, that while the episode of “This is Us” is sad, it’s “beautiful.”

“If I think about it, I will cry right now,” she said. “I saw a screening of it last week and I almost had to excuse myself...I need to not ever be around people when I watch. It’s so beautiful.”

This is hardly the first time “This is Us” cast members have teased the flashback episode. On Jan. 8, Milo Ventimiglia — who plays Jack on the show — revealed to The Hollywood Reporter that viewers could expect an episode centered on Dr. K (Gerald McRaney) in the future. He said the episode would delve deeper into one from the pilot, which showed Rebecca and Jack in the hospital after delivering the triplets, one of whom did not survive. Ventimiglia recalled that the scene was muted, meaning viewers couldn’t hear what his on-screen spouse was saying. He added that the episode would serve as another piece to the puzzle that has been Season 1 of “This is Us.”

“The scene in the pilot from the hospital with Rebecca was muted and viewers didn’t hear what we say, so we had never seen that,” he said during the Television Critics Association’s winter press tour. “So seeing it, it was one of those things where you forgot about it. It was like finding this favorite pair of socks in a drawer and putting them on and wiggling them around. That was the silliest analogy...but it was very fun to see it.”

It’s not clear when this episode will premiere. “This is Us” airs Tuesdays at 10 p.m. EST on NBC.