I once watched a mediocre horror film called “Phantasm III,” whose final scene contained one line that’s echoed in my consciousness ever since.

The film’s final two survivors huddle in a darkened room, gasping with relief after having dispatched the “monster,” a black-trenchcoated man with supernatural powers. One of the survivors, standing with his back to a large window, smiles and says, “It’s finally over.”

At that moment, the villain smashes through the window, wraps his hand around the boy’s face, and snarls in his ear, “It’s never over.”

Cut to black. End credits.

Throughout my life, that line, “It’s never over,” has whispered itself in my mind’s ear, both at funny moments (the middle of a hard workout or a boring class) and at times that strike me as a little more poignant (another month behind on the rent; another return to singleness). One reason for the quote’s near-universal applicability seems to be that it laconically states a fact of life: History has a tendency to repeat itself. With all respect to the philosopher Heraclitus, the truth is that we seem to find ourselves stepping in the same rivers over and over again.

“True Detective” runs with this idea — both into more cosmic territory than many novelists would consider, and also deeper into humanity’s heart than most cosmologists would probe.

Very slight spoilers ahead.

Take, for example, the interrogation that rehashes the day when detectives Hart and Cohle extract a pair of sexually abused children from a shipping crate. Reflecting back on that day, Cohle muses, “That boy and that girl are always in there. Always have been; always will be.” His implication, as he makes clearer over the course of the episode, isn’t merely that children continue to be sexually abused. It’s that, given enough time, no amount of rescuing can prevent those specific children from ending up back in that specific crate —whether in this universe or in some future one.

“True Detective” isn’t the first piece of writing to explore the horror inherent in this idea of eternal recurrence — as early as 50 B.C., the Roman philosopher-poet Lucretius wrote, “All things are the same forever … yea, thou never diest.” But as far as I’m aware, this show is the first piece of fiction to explore the human implications of the idea to their bleakest logical limits.

To be clear, this idea runs far deeper than the old saw that “nothing ever changes.” Given enough time to change, the configuration of matter and energy that comprises this present moment will eventually end up right back where it is now. This is no Hindu karmic cycle, in which all beings climb the ladder to liberation life-by-life — in fact, as the philosopher Arthur Schopenhauer wrote back in 1818, eternal recurrence on this ultimate scale must actually be a kind of hell; an inescapable carousel fueled, at bottom, by blind lust.

Hinduism does teach, after all, that this universe itself is gradually winding down to a state of total chaos, from which the next universe will be born. And so on, through the next universe and the next, off into infinity.

Even in modern physics we’ve got two basic choices: Either the universe fizzles out into eternal nothing, or it eventually recondenses into a “Big Crunch” from which the next Big Bang explodes. And unless there’s some unknown dead end for existence itself — some hard limit at which everything just stops for good — then the universe’s atoms (or those of some future universe) will eventually reassemble in such a way that those children will be locked in that shipping crate again. And again, and again.

Mankind could sculpt the entire galaxy into a humanitarian paradise by the time this universe burns out, and it wouldn’t change a lick about what happens afterward. Given infinite time and the existence of infinite cosmic reboots, the return to the same is logically inevitable.

Hell, a single monkey poking at a typewriter for eternity will eventually type out the works of Shakespeare via sheer random chance.

Recurrence seems to have fascinated us humans long before we speculated about Big Bangs or multiple universes — or about karmic cycles, for that matter. Stone-age art around the world abounds with spiral patterns — some of which are themselves repeated over thousands of years on the same rocks. Anthropologists have speculated that these symbols may refer to the concept of eternal recurrence, and/or that they may have served as magic charms, intended to keep enemies or prey animals wandering in futile spirals.

“True Detective” asks, In the really long run, what’s the difference?

Ben Thomas is a blogger for Scientific American, TechRepublic, HuffPost, Nature, Discover, Forbes, etc. Follow on Twitter: @writingben