If you haven’t watched all of “True Detective” through last week’s episode, be warned of spoilers ahead.

Thanks to “True Detective,” people are quoting Matthew McConaughey again. Because, as he will demonstrate with a mangled beer can, “time is a flat circle. Everything we’ve ever done or will do, we’re gonna do over and over and over again.”

“True Detective,” the runaway HBO hit about two Louisiana cops chasing an elusive evil for two decades, wraps up its first season on Sunday. Rustin Cohle (McConaughey) and his old partner Marty Hart (Woody Harrelson) are all set to nail down at least one part of whatever awfulness is coming.

The show, set to end its story after eight hourlong segments, has been analyzed at “Breaking Bad” levels of delightful, annoying geekdom, making it the latest frustrating, intricate TV drama turned social experiment.

Sunday nights have a lot of shows like that, because Monday mornings go down easier with a round of “Did you watch? Are you caught up?” My work friends, bless their hearts, maintain a spoiler-free zone — within reason. Don’t be saving the “Game of Thrones” finale for four days, that’s just rude.

“True Detective” deserves most of the effusive praise it’s getting, managing to be dark, sexy, terrifying and sad, sometimes all at once. Rust’s flat, detached manner of talking about his baby daughter’s death cuts deep.

“The hubris it must take to yank a soul out of nonexistence, into this meat,” he muses. “And to force a life into this thresher. Yeah, so my daughter, she — uh, she spared me the sin of being a father.”

Shows like “True Detective” swarm your Facebook feed, and given the chance to actually catch up, eventually you join the other drones reconvening at the hive (Twitter, et al.) to toil with singular intent (parsing Townes Van Zandt lyrics).

If only Reddit had been around for “Twin Peaks.” Fans had to find each other at parties by dropping obscure references to chewing gum and midgets. Rows of VCR titles were prominently displayed in dorm rooms. It was a simpler time.

In one David Lynch-esque moment of “True Detective,” birds flock into a replica of a victim’s spiral-shaped tattoo in a nearby field. Symbolism can be its own reward, especially in a story being told by guys who hallucinate and drink until dawn.

Still, the kind of unreliable narrator who would steal coke from the evidence room — with Lucinda Williams on the soundtrack, no less — invites scrutiny, and thus began the amateur and professional dissection of the show, especially McConaughey’s character.

The way series creator Nic Pizzolatto tells it, even Rust would say, “Y’all are over-thinking things.”

“Like, why do you think we’re tricking you?” asked Pizzolatto in a recent Daily Beast interview. “It’s because you’ve been abused as an audience for more than 20 years.”

And yet, “True Detective” is stuffed with visual meta-narratives that disturb without enlightening. The finale’s preview capsule merely says that “an overlooked detail will provide Hart and Cohle with an important new lead in their 17-year-old case.”

Just one detail? Where to begin? How about that red mark on bad guy Reggie Ledoux’s forehead? It looks a lot like the one on the Marshland Madea, the supposedly unrelated murdering mom Rust advises to kill herself after she signs her confession.

When Rust goes to visit the only survivor of the shadowy forces along the bayou, why is the mental hospital’s flower mural a replica of the artwork in his partner’s bedroom?

We’re supposed to notice that Marty is watching “The Searchers” while he eats his Lean Cuisine, right? The movie where John Wayne tries to rescue a little girl from a guy named Scar. Got it.

All of this feels a lot like Megan Draper on “Mad Men” wearing Sharon Tate’s T-shirt: Take note, feel smart, but no one really expects the Manson Family.

These diversions are more welcome here, actually, because the “True Detective” universe is finite. As absorbing as these cops are, eight hours is plenty of time to spend with their bourbon and cigarettes, hot- and cold-blooded violence and “Apocalypse Now” jungle hangouts.

So if the mysterious villain the Yellow King turns out to be a fire, or the sun, or a sheet of blotter acid, or that fast-food joint from the end of Episode 5, no big deal. Sometimes the breadcrumbs go in a circle.

I don’t even need to know why Rust never sleeps. But Marty’s daughter Audrey? She has some explaining to do.

The little girl’s sinister doll play and disturbing sexual drawings evolved into unfortunate amounts of eyeliner and risky teenage sex. The implication that she was, at least, a witness to something awful is not just a figurine on someone’s table. Audrey would be the worst string to leave untied, and exactly the kind of trickery Pizzolatto denies.

“My life’s been a circle of violence and degradation, as long as I can remember,” Rust announced last week as he and Marty worked on a plan that included a parish sheriff, a boat and jumper cables. “I’m ready to tie it off.”

But he has this one last thing.

There’s a reason, beyond the possibility of a Special Agent Childress or Tuttle in the shadows, that Rust has not turned over his storage unit full of evidence — including a videotape! — to the FBI.

Rust is just like everyone who has watched this far: He wants to be the one who figures it out. But it’s not all going to get figured out, ever.