Close Encounters of the Third Kind is Steven Spielberg’s family-sized late-70s UFO drama, starring Richard Dreyfuss as a midwestern Joe Schmoe who sees coloured lights in the sky and starts sculpting his mashed-potato into the shape of Devils Tower in Wyoming. It was, at the time, Columbia Pictures’ highest-grossing blockbuster, and it proved the director of Jaws was no flash in the pan. Close Encounters was fantastical and mystical and sometimes borderline hysterical. And it was, for a few years, my absolute favourite movie.

Pauline Kael described it as “a kid’s film in the best sense”, and she was absolutely right. Except, the first time I saw it, aged eight or so, it seemed impossibly sophisticated, gob-smackingly profound and as much a guide to the perplexing world of adulthood as it was to the galaxies above our heads. It contained messy homes and messy cars and a psychologically messy hero in electrician Roy Neary (Dreyfuss), who undergoes a Damascene conversion on the backroads of Indiana and returns home a wild-eyed zealot to spook his kids at the dinner table. “I guess you’ve noticed something a little strange with Dad,” he tells them through the tears. “It’s OK, though. I’m still Dad.”

Facebook Twitter Pinterest Richard Dreyfus as Roy Neary, having a Damascene moment. Photograph: Channel 4

How strange to learn that Spielberg actually wanted Steve McQueen to play the role. That would have made it a totally different film – the tale of a rugged all-American turned intergalactic pioneer, as opposed to an everyman in mortifying meltdown. Obviously Dreyfuss was the more interesting choice. He makes Neary grey-faced and rumpled and somehow older than his years; hot-wired by an obsession he can barely put into words and torching his career and his marriage without so much as a backward glance. As played by Dreyfuss, Neary doesn’t rise to the occasion so much as descend to it, digging himself deeper and deeper into trouble before finally slipping down the mountainside to meet the alien mothership. In the view of the French government scientist played by François Truffaut, Roy Neary is a hero. In the view of everyone else, he’s taken leave of his senses.

At the time, the Devils Tower finale was billed as the film’s big bells-and-whistles showstopper. Viewed today, it feels over-extended, a tiresome piece of prog-rock noodling that one is tempted to watch on fast-forward. But as for the rest: well, it’s still kind of wonderful; a storm of dustclouds and summer crickets and vast star-splashed skies. I love the breadth and business of Spielberg’s picture. I love the din of different languages; the cross-fire of conversation (Robert Altman got there first, but I didn’t know that at the time). Close Encounters is sunnier and simpler than the other great American films of its era. But it contains enough angst and confusion to keep it the right side of sappy.

Rewatching the movie, I’m wondering exactly what quality hit me so hard as a child. Was it the tantalising prospect of first contact with space aliens? Or something smaller, knottier and altogether closer to home? The first time I saw it would have been shortly after my parents’ divorce. These days that feels significant. Close Encounters is a film about a dissatisfied young father with one eye on the exit door. It also contains a frayed, exhausted single mum (played by Melinda Dillon) who suspects she can’t protect her infant son. No doubt this would have sailed over my head at the time, but it seems likely that on some level I recognised my parents on the screen – and caught the faintest, fleeting understanding of how their lives were playing out.

Also Close Encounters painted a compelling picture of planet Earth – the alien land I’m still trying to figure out to this day. Like every childhood favourite, it was a formative film, a gateway of sorts, opening out towards thornier, scarier, wilder views. I remember being especially struck by the scene in which Neary first encounters the extraterrestrials, when the power grid fails and the mailboxes start rattling and all the truck’s clutter blows into the man’s face. Spielberg made the adult world feel so rickety and impermanent, barely tethered to the ground and liable to be torn loose at any second. This was terrifying but it was thrilling too. It allowed for the possibility for transformation and adventure, hinting at a chaotic magic that might be hiding in plain sight.

That’s probably why I never really liked the film’s ending, when Neary is willingly led up the gangplank to the mothership. He’s leaving the weird-looking mountain and the new friends he has made. He’s leaving the backroads, the deserts, his family, the forests. He’s leaving the untidy homes, messy cars and all those unpredictable people – and having sat through the film, I could never understand why he would. Because what was all that if not a comical abundance of riches? And who needs the cosmos when you’ve got a world like this one?