There's a new type of heartbreak on This Is Us. In the above sneak peek, Rebecca (Mandy Moore) finally meets Nicky (Griffin Dunne), the estranged brother that her beloved Jack (Milo Ventimiglia) kept secret from her for his entire life.
"I had to take a big deep breath before those scenes," Moore told us about preparing for Rebecca to meet Nicky.
Moore, who is working with Nature's Way, said one of the reasons she had to mentally prepare for the scene was because of her scene partner, Dunne, a "just a remarkable actor."
"I knew that I was coming into this really tricky situation where I'm upset and I'm angry at someone who is no longer around to be upset and angry with, they kept this secret from me and kept this family member a mystery and hidden from all of us," Moore said. "It was complicated."
Moore said she kept Justin Hartley's character, her TV son Kevin Pearson, in mind while doing those scenes because her character needed to be there as a mother. But still, Rebecca was grappling with her own feelings, as you can see in the clip above.
"Oh, she felt completely betrayed, but nowhere to put those feelings," Moore said. "It's such a helpless feeling."
Click play on the video above to hear more from Moore and see the exclusive sneak peek up top. Be sure to come back to E! News for more This Is Us after the Tuesday, Feb. 12 episode.
This Is Us airs Tuesdays, 9 p.m. on NBC.
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