Rectify is the best series I have ever seen on television. Not may be. Not might be. It just is.

I’ve tried to think of another way to say that, because I distrust categorical statements, even my own, and because I realize what an impossibly broad subject TV is. But I couldn’t work it out any other way. Every time I tried to qualify that claim (Best dramatic series? Best network series? Best narrative about an ex-con?), I betrayed my own enthusiasm.

For anyone coming in late, Rectify begins its fourth and final season tonight. In the opening episodes, Daniel Holden, the story’s protagonist, has moved to a halfway house in Nashville and gotten a job in a warehouse, after being banished from his hometown in Georgia. The banishment was part of a deal in which Daniel pleaded guilty to murdering his girlfriend 20 years back. The plea in fact settled nothing. We still do not know if Daniel murdered Hanna Deane and neither does he (the circumstances are, at best, murky).

I could go on filling in the details of the plot, but that’s sort of pointless. Stuff happens in this series, plenty of stuff, in fact, but the plot is not the important thing. Or put it another way: plot is way back in the pack behind character and circumstance.

The entire series, in fact, is spent answering the question, what happens to a man who gets released from prison after serving 19 years in solitary on death row for a crime he may or may not have committed? What happens to his family when he returns home, or the people in his town?

Rectify takes its own sweet time answering these questions, and some of the answers change and then change again. I can’t recall a series where your opinion of nearly every major character does a 180 and sometimes a 360 over the course of three seasons. This is not a mark of indecisiveness, but a true signal of the show’s depth: the characters themselves change as they absorb the new reality created by Daniel’s release, but so do our ideas of who they are. We think we know them, but we learn better as things unfold.

It’s slow and quiet—everything TV usually isn’t—and that’s a good thing. As guided by show creator Ray McKinnon and anchored by the devastating performance of Aden Young as Daniel, Rectify takes advantage of its glacial pace to make room for scenes that we’re simply not used to seeing in television shows, or movies either, for that matter.

At one point in Season 1, Daniel accompanies his mother to WalMart. There, in that commonplace shrine to mass consumption, he is nearly overwhelmed by the plenitude of what he sees. Video games, plastic storage bins, and endless balls of yarn mesmerize him as though he were an alien. But in a scene typical of the subtlety with which McKinnon and his crew approach their story, Daniel and his mother do not discuss his alienation outright but rather engage in a wry dialogue about their next move (“It’s time,” he says, wandering down one aisle. “Time?” his mother asks. “Time we got into yarn,” he says). Here, as elsewhere, things do not go where you think they will go, and the people, as people will, surprise you.

I don’t know if the decision to end with this season is a bow to the demands of the Sundance Channel, or if this is how it was planned all along. I like to think it’s the latter, that McKinnon envisioned a story that would take four seasons to tell, and quit when he’d accomplished that goal. If he didn’t, then he hid his tracks very well, because the story so far feels organic, fated almost, as though what has happened is the only thing that could have happened.

My gripe with most TV shows, especially the best ones, is that at some point, usually in Season Two or Three, they turn into regular TV shows. That is, even with top-drawer material, like The Sopranos or Breaking Bad, the very success of the show works against it: after a while, you know that nothing too awful is going to happen to, say, Tony Soprano, because Tony is the star. He might as well be Marshall Dillon or Captain Kirk—indestructible as long as the ratings hold up.

Rectify has never fallen into that trap. Without a trace of coyness, it keeps you guessing. I wouldn’t bet so much as a dime on the fortunes of any of its characters, because I don’t know what lies in store for them any more than they do. I do know that everything that has happened so far has a convincing ring of truth. It is hard not to believe they are real—and while you’re watching, it’s impossible. That alone is more than I can say for any other show I’ve ever seen.