If Captain Fantastic had come out nine years earlier, you'd suppose it was a minimally inspired Little Miss Sunshine knock-off: a colorfully eccentric family travels across These United States in a vehicle unapologetically nostalgic for the 1960s (a refurbished school bus named "Steve", decked out in hippie decor, in this case), with a misfit teenager (George MacKay even looks like an ersatz Paul Dano) and cute little moppets behaving a bit too much like adults without having a clue what they're actually saying. Instead, it premiered at Sundance a whole ten years and three days later than Little Miss Sunshine, and thus rather than feeling like a halfway-adequate trend-hopper, it more resembles some kind of misplaced archaism, a Quirky Indie Crowdpleaser™ that's years too late for the party.

The quirk about this particular family is that the dad, Ben Cash (Viggo Mortensen), and the mom, Leslie (a barely-seen Trin Miller), were so invested in the anti-capitalist, anti-consumerist words of the great left-wing philosophers that they decided to raise their brood of six children in the woods of the Pacific Northwest, living off the land and eschewing every last trapping of modern American culture, like television or prepared food. But Leslie suffered from bipolar disorder, not helped out by her isolation from the world, and she had to leave the family behind for a time. While out in the world, she committed suicide. Now, Ben and the kids, ranging from 18-year-old Bo (MacKay) down to little Nai (Charlie Shotwell), are off on a road trip to attend Leslie's funeral, where they shall enforce her last wishes (to be cremated in a no-big-deal ceremony) against the wishes of her normie Christian parents (Frank Langella and Ann Dowd).

The script, by second-time writer-director Matt Ross, plays around with a lot of big words and famous leftist names, but it's strictly an affectation ("Trotskyist" qualifies as a deep cut), mostly so for the ostensible pleasure of watching little children mouth boilerplate anti-capitalist sentiment. But the film isn't terribly interesting in exploring the ramifications of its ideas at all, nor digging into politics in more than the most superficial way: the ultra-famous (by the standards of academic philosophers) Noam Chomsky is the only living writer to be so much as named-dropped. And it's certainly not interested in hosting a debate, propping up Traditional Values in the form of Langella, or Ben's dopey suburban brother and sister-in-law (played by Steve Zahn and Kathryn Hahn), only long enough for them to be smugly shown-up, or outright ignored.

No, the name of the game here is strictly "watch as the free-spirited dad defends his kids, then realises he's possibly fucking his kids up, then decides that nope, everything is aces", with the usual artificial and quickly-resolved roadblocks that provide the least-possible obstacle to the audience's ability to enjoy the characters being their adorable selves. It's all slightly intolerable, salvaged minimally by cinematographer Stéphane Fontaine's beautiful shots of the Washington woods, and given a far-too-committed performance by Mortensen, who has decided to treat his role with respect and gravity that make the whole movie feel much more serious and consequential (the same is even more true of Langella, who is so earnest in his portrayal of a concerned grandfather that almost threatens to make this a genuine discussion of the moral dimension of child-rearing), though I'm honestly not sure if the film is better off because of it or not. Otherwise, this is all forced whimsy that did something I wasn't aware could happen: it made me want to slap people upside the head for how much they like Chomsky.