'This Is Us' Season Finale Sneak Peek: Watch Rebecca Unsuccessfully Try to Get Ahold of Jack

See a preview of what's to come on next week's episode of the hit NBC series.

Warning: Spoiler alert! Do not proceed if you have not watched Tuesday’s episode of This Is Us. If you have, read our full recap.

The first season of This Is Us is coming to an end, and ET has your first look at what's to come during the highly anticipated finale!

At the end of Tuesday's episode of the popular NBC series, fans were shocked when Kate Pearson (Chrissy Metz) told boyfriend Toby Damon (Chris Sullivan) that it was her fault her dad, Jack Pearson (Milo Ventimiglia), died. While we still don't know exactly what led to the Pearson patriarch's death, fans were left with an image of a clearly buzzed Jack getting into the driver's seat of his car after a night of drinking with co-workers at a local bar.

WATCH: Milo Ventimiglia and Mandy Moore Say It's 'Not Fun' Playing Jack and Rebecca's 'Worst Scenario'

In a sneak peek clip from the finale episode, Rebecca Pearson (Mandy Moore), clad in a gorgeous sparkly gown and bouncy curls, tries to call Jack on a pay phone during a break from her two-week, five-city tour. Unable to reach him, she begins to panic.

"Jack, are you home?" Rebecca exclaims, leaving a voice message on their home answering machine. "Ah, I was hoping you would be there. I miss you. And I wish you were here, or I wish I was there. I love you. I'll call you later, OK? Bye."

See the full clip in the player above.

Following Tuesday's episode, Ventimiglia admitted to ET that filming these types of scenes weren't very "fun."

“We're very tight," Ventimiglia said of his on-screen wife. "Our chairs are next to each other. We talk a lot in between takes and whatnot, and the days that we have to play very distant, they’re just not fun to film."

The This Is Us season finale airs next Tuesday at 9 p.m. ET/PT on NBC.

WATCH: 'This Is Us': Kate Drops a Huge Bombshell About Jack's Death