This Is Us star Justin Hartley teases 'unpredictable' series finale

Now entering the heart of its fifth season, This Is Us still has plenty of drama to unspool, twists to uncork, and tears to spill, but NBC's time-tripping family drama is indeed inching closer to the end of its run. Creator Dan Fogelman has talked for a while now of a six-season journey for the Big Three, when "the Pearson story will basically come to a close."

Justin Hartley — who stars as charmed, self-defeating, and striving actor Kevin Pearson — isn't quite ready for the final strokes of the painting to be set in stone, if we may mix metaphors and mediums. Hartley quips to EW that he is even open to a four-decade run, "as long as we're still telling this story and as long it's compelling. If it takes 70 years to tell this story, I'll be around for the next 30 of them, probably 40. But I love how the story is unfolding and I love being a part of it. So I'll do it as long as they let me."

The show's big goodbye has actually been years in the making. The producers started prepping for the finale a few years ago, banking scenes with the younger versions of the Big Three to capture the actors at those specific ages. And the adult cast members have had an increasing sense of how this multigenerational, multi-era story wraps up, thanks to their giddy creator. As stars Milo Ventimiglia and Mandy Moore recently explained, Fogelman turns into a little kid as he excitedly doles out puzzle pieces to them as the endgame percolates in the writers' room. And he has always shared ideas of where the story was headed, according to Hartley: "From the beginning, Dan has always said, 'Whatever you want to know, I'll tell you."

Ventimiglia told EW that the end of the series would be "amazing," "magical," and "hopeful," while hinting that the show "morphs into something we could not dream or imagine it would become." Hartley agrees with that assessment, noting: "I think it's very unpredictable." He offers this assessment: "The way that the story has been told to me and the way that it ends seems like the right way to 'end' it. Just like life, everything does end, doesn't it? I think it's full. You're going to have a full heart, just because by that time you will have watched these people and all of their journeys for such a long time. When you invest that much as an audience member, you'll fill up completely, but in satisfying way… It's definitely an emotional journey, and we have a lot of laughs to be told in it. I mean, there's funny stuff coming up as well."

Speaking of which, here's Hartley's teaser for the finale. "Milo told you about the spaceships, or no?" he deadpans. "Can you imagine? How we go past six seasons is we all become vampires — and then we do another 16 seasons and we don't age."

You can sink your teeth into a new Kevin-centric episode of This Is Us on Feb. 9, when he encounters danger on his way home from Vancouver to be with his now-in-labor fiancée, Madison (Caitlin Thompson).

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