At this point, 12 seasons and 246 episodes into its run, Bones is probably best known to TV fans as a punchline, either about its surprisingly long run, despite never being a megahit, or about its kinda goofy title, which the show gets from its protagonist, forensic anthropologist Temperance “Bones” Brennan, played by Emily Deschanel. (That character name is one of the few remaining links in the show to its origins as a series of Kathy Reichs novels.)

But don’t let the show’s long run and/or goofy qualities deceive you. At its height, Bones was a genuinely entertaining crime drama, with solid mysteries of the week, good team banter, and a will-they/won’t-they romance that kept the show humming. I was never that into the question of whether Brennan would hook up with her handsome, David Boreanaz–portrayed FBI agent friend Seeley Booth — those names! — but it certainly gave the show a continuing hook.

What’s more, it suffered the aging that affects all shows this old, but it never got truly bad. You could tune in to a random episode of Bones in a later season and still have a pretty good time.

Bones ended its run forever Tuesday, March 28, though it will now presumably live on for decades in cable syndication and on streaming services. But for any show that lasts that long, there has to be some point of attrition, right? Where was it for Bones?

I can pinpoint the exact moment when Bones took one step too far and became a show I knew would never quite satisfy either me or itself. Bones was a good show — but it wanted to be more, and that came back to hurt it.

A season-finale twist pushed Bones to a place it didn’t know how to escape

Both the blessing and the curse of Bones was its high level of ambition compared with most crime dramas on the air. Rather than settling into a rut of happily solving a new case every week, Bones would put on theme episodes (including a truly strange hour set inside a dream). It would tease out the Booth/Brennan romance. It would take stabs at serialization.

All of this was in keeping with the show’s two major influences, Moonlighting and The X-Files, but it also reflected creator Hart Hanson’s impish sense of humor and desire to have fun with his show and his characters. There was nothing on Bones that couldn’t be subverted — especially if the jokes were good enough.

But that also sometimes meant the show felt as if it were on shaky ground when it came to its supporting cast. Booth and Brennan stayed relatively consistent — he was the surprisingly emotional man of action; she was the completely rational scientist with a sneaky soft spot at her core — but the show would often try out a bunch of different things with its supporting players until it landed on one that worked. In the early going of a show, that’s natural and understandable — but Bones would often keep going for seasons at a time.

This ambitious quest reached its zenith in the show’s third season finale, “The Pain in the Heart,” in which Brennan learned that her long-suffering lab assistant Zack Addy had collaborated with a serial killer in order to destroy the world (or something). It was a strange plot twist, to say the least, and it made less and less sense the more the show tried to explain it. The show’s quest for a big-stakes, serialized story — the serial killer’s actions had driven much of the season — ran headlong into its tendency to redefine supporting players’ motivations on a whim, and the results were one of the show’s weakest hours.

None of that made Bones a bad show. As mentioned, it remained quite watchable up until the end, and its fourth season was still quite good (if not at the level of seasons two and three). Even the series finale, though forgivably cheesy, has its moments. But it did suggest that the series was always going to have grander ambitions than being “just” a show where lab techs solve crimes by looking at bones.

There’s nothing wrong with grander ambitions, and they often kept Bones from turning into yet another show about mismatched romantic partners trying to solve crimes that slowly ran out of story to tell as its central couple endlessly circled each other. Bones could put off pairing off Booth and Brennan for several seasons because it could always fall back on other, bigger ideas.

But the Zack twist still cracked something open inside of the show, making it all the more obvious that the series would sell out its characters for the sake of a plot twist. Everything on Bones was malleable, but never in a way that felt like somebody understood exactly why and how to change its core. It was a good show that wanted to be a great one, but it didn’t quite know how to get there.