Credit: Lisette M. Azar/CBS

Big Brother made headlines early this summer when several houseguests were caught on camera saying racist things. The surprise was not the racism. More than a few people probably didn’t realize that Big Brother was still on. Over a decade ago, CBS radically shook up its stodgy, over-48, Diagnosis: Murder image by debuting three reality TV shows that survive to this day. One of them was Survivor, an addictive zeitgeist sensation which became one of the last genuine broadcast-TV megahits in summer 200. It remains a reliable attraction; its ratings have diminished, but after 26 seasons, it has also outlasted whole generations of ripoffs. The Amazing Race debuted in 2001, and can lay claim to a different sort of glory: In the ten years that the Emmys have awarded a Reality-Competition Series, Amazing Race has won nine times. (The one time it lost was to Top Chef, which in Reality-Competition terms is sort of the Sopranos to Race‘s The West Wing.)

Big Brother debuted the same summer as Survivor, but it never had that show’s success or Race‘s critical acclaim. In hindsight, the first season of the show looks like a hodgepodge of turn-of-the-millenium Big Ideas. A new episode ran basically every night of the week throughout the summer — this was the moment when ABC’s decision to run Who Wants To Be a Millionaire? three times a week was a ratings-grabbing success story and not yet a lineup-demolishing catastrophe. The show was draped in the social-experiment philosophizing that was still a hallmark of reality television before the genre went full-cartoon. You could watch live feeds from inside of the Big Brother house for free on the website, assuming you had a strong enough internet connection to watch video. The show was hosted by Julie Chen, a host who vibed like a Dunkelman. The show had low ratings, but hell, it was summer; CBS renewed it for a second season.

Time passed, and reality TV became what reality TV is now. Precisely what that is still isn’t really clear. Reality TV is a ratings juggernaut and is one of the defining genres of the last decade, as prevalent (and maybe even more influential) than the post-Sopranos antihero drama. Reality TV is how you build empires: Bravo, E!, A&E, post-music MTV, Fox post-2003 and NBC post-flameout all owe their modern existence to the genre. Some reality shows become gigantic hits and then flame out quickly; others become gigantic hits and then become institutions.

Reality TV isn’t quite respected yet, but over time, a generally agreed upon pantheon of great reality TV shows has emerged. Survivor is in there certainly, and The Real World before it became a parody of itself (although there’s a school of thought that loves the parody — and in that school, The Challenge is the genre’s masterpiece.) Top Chef and Project Runway brought a sense of style and class to reality TV; Joe Millionaire and My Big Fat Obnoxious Fiancé spoofed the genre masterfully. At their best, reality TV shows have created a whole bizarro-universe, built a series of tropes that aren’t so much clichés as totemic signifiers of the shows’ semi-invented world; at this point, The Bachelor has a mythology to rival Tolkien, while The Real Housewives is a spinoff-wellspring mega-franchise comparable only to Star Trek. (New York is the Deep Space Nine.) You could swap in The Biggest Loser if you love crying, or Jersey Shore if you love trashy decadence, or Duck Dynasty if you love America.

Big Brother usually never enters that conversation. Until this season, the show was a relatively quiet elder statesman, confined to CBS’ summer season; it aired three nights a week, which probably kept away casual viewers (even as it energized obsessives.) Unlike the glossy Survivor and the classy Amazing Race, Big Brother is inexpensive, shot entirely inside of a house that resembles one of the cheaper sets from early ’90s Nickelodeon. (It’s also the rare show that isn’t shot in HD; your average toddler’s birthday party uses better cameras.)

Maybe it’s time for the conversation to change. Last night marked the show’s 500th episode. The show’s ratings are up this season, which admittedly could be a controversy-assisted fluke — and the few racist comments that actually made it to air were genuinely disturbing in a way that the look-how-PG-crazy-this-is mode of most reality TV would never allow for. This hasn’t even been a particularly good season: The stupid hot idiots who dominated the game early on were quickly expelled and replaced by passive non-participants who have been slowly picked off by a single powerful alliance. It’s a serious qualitative step down from last season, which featured the fever-dream escapade that was Coach Dan’s Funeral; or season 13, which starred the possibly insane Rachel Reilly and basically transformed her over the course of a single season from Joffrey Baratheon into Luke Skywalker. Like most long-running reality shows, Big Brother has trended crazier, with more twists, more returning housemates, and more controversy.

At the same time, I think this summer of controversy hides a deeper truth: 15 seasons in, Big Brother has proven to be one of the most resilient concepts of the reality TV era. In one sense, the show is fantastically rigid. Each week, the housemates compete in a Head of Household competition; whoever wins is basically the house King for a week, allowed to live in the luxurious HoH throneroom. The Head of Household nominates two members of the house for eviction; those nominees compete in a Veto competition, and if they (or one of their allies) wins, they can come down off the block. After a final vote to evict, the whole process repeats — and whoever was HoH that week is not allowed to compete.

In the best seasons, the power structure of the house essentially reboots every week. Someone who was nearly sent home can win HoH and immediately take revenge on their enemies. A heretofore powerless player can win HoH and suddenly become the house rainmaker — and if they anger the wrong person, they might find themselves in the sniper scope the following week. The HoH/Veto/Eviction structure is clockwork-tight, but Big Brother also operates according to Calvinball non-rules, throwing in new twists just because and occasionally just changing the rules for the hell of it. (A couple weeks ago, the show allowed four evicted castmates to compete for re-entry, almost certainly as a way to get fan-favorite nice guy Judd back in the game.) This makes the show frustrating, but also adds to the sense that the power structure in the house can change at any given moment.

What makes Big Brother both unique and great is that, as the power dynamic shifts, so does your perspective on the house. A lovable underdog can become a villainous powermonger, and vice versa. Because Big Brother airs on television concurrently with the housemates’ imprisonment, the show’s editors don’t have a long post-production cycle to decide who they’ll present as a hero or a villain; the end result is something which feels a little bit more like genuine truth, if only because the producers don’t have enough time to get their lies straight.

Even better, the racism controversy this season highlighted one of the best thing’s about Big Brother‘s bifurcated existence as a Television and an Internet experience. The show was ahead of its time in at least one respect: The live feeds which were free way back in 2000 are now a subscription service on CBS’ website, and feel specifically designed for the kind of hyper-engagement that is the hallmark of our age of pop cultural mega-obsession. (Big Brother had a second screen back when people could only handle one.) The only reason why the housemates’ racist remarks appeared on TV was because an outcry erupted online among fans who were watching the feeds. That outcry hasn’t died down and probably never will: People who watch the feeds are constantly complaining that people who just watch the TV show are missing out on a huge amount of context and subtext. (Not to keep throwing out Game of Thrones comparisons, but it’s reminiscent of how people who read the original “A Song of Ice and Fire” books will always insist that people who just watch the HBO TV show will never get the full story. Which is a statement as true as it is annoying.)

In some respects, the show has gotten better as the years have passed and the campy elements have been embraced. The competitions get loopier (and more fun). And Julie Chen has leaned into the Chenbot thing; maybe it’s the success of her daytime series The Talk, but her awkwardness looks more endearing every year. (It helps that she has perfected a Leslie Nielsen tone of voice which sounds hyper-serious and sarcastic.) But at heart, the best thing about the show is how unadorned it is. It’s a show about people cut off from society, with nothing to do for an entire summer except plot and counter-plot; with each passing week, you can actually see them become a little more unhinged, as cabin fever sets in and emotions run higher and higher.

Visually, the show feels unique: While most reality television has embraced the handheld camera (and the presence of an implied just-offscreen camera crew), the camera on Big Brother is defined by the steady pans of a surveillance camera. t gives Big Brother a slightly haunted feeling, as if people on this show are simultaneously utterly alone and surrounded by an angry mob. Most of the important conversations happen in whispered tones, with subtitles, as players plot against each a housemate who quietly eats cereal one room away.

Even if this season hasn’t been the best — even if the show falls victim to the impulse towards caricature, like too many other reality TV shows — Big Brother just turned 500 and has arguably never been more important in the TV landscape. It’s an eerily addictive deconstruction of power, a competition about people who do nothing except dream of ways to betray each other, and a portrait of humanity in extremis that feels a little bit like a political satire and a little bit like war.