'This Is Us' Fall Finale Sneak Peek: Is Kevin About to Push Nicky Away for Good? (Exclusive)

ET exclusively debuts a first look from Tuesday's Thanksgiving episode.

It's Thanksgiving in the Pearson household, which means family tensions are about to come spilling out at the dinner table. 

On Tuesday's fall finale of This Is Us, titled "So Long, Marianne," the expanding Pearson family spends the holiday for the first time at Randall and Beth's new Philadelphia home, and only ET has the exclusive first look.

In the sneak peek, Kevin (Justin Hartley) drops by Nicky's (Griffin Dunne) trailer to pick him up for the long drive from Bradford, Pennsylvania, to Philly. But Nicky expresses uncertainty over him joining the whole clan for turkey dinner, as he nervously smooths out his baby blue zip-up sweater in front of the mirror.

"I look like I'm in a Viagra commercial," Nicky deadpans after Kevin compliments his "sharp" look.

"You do not," Kevin says with a laugh. "You look newly sober chic."

Nicky, though, looks as if he's about to be sick -- his nerves over crashing the Pearsons' annual Thanksgiving tradition weighing on him heavily as he mutters, "I'm not so sure about this..." Kevin, of course, hilariously thinks his uncle is talking about his un-Nicky-like pleated dress pants, forcing Nicky to hastily cut to the chase.

"I'm not talking about pleated pants, you nitwit, I'm talking about coming to your brother's for Thanksgiving... with your whole family...," Nicky forces out.

"It's going to be perfect. Trust me," Kevin assures him with an amused smile.

But when Nicky asks about Kevin's trailer that's been parked next door for the last several weeks, subtly hinting that maybe it's time for him to go back to his life in Los Angeles, the former Manny star proposes an unexpected solution.

Could Nicky's reaction to his idea, however, be the straw that breaks the camel's back and pushes Kevin -- who's been by his side through thick and thin -- away for good? Watch ET's exclusive sneak peek above to see what happens next.

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

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