There are serious spoilers below for the entirety of Gravity Falls, and spoilers are a huge part of this show. If you haven’t seen it, go watch it. It’s all on Hulu. You’ll be doing yourself a big favor. If you’ve already seen it, or you just have no appreciation for surprise and wonder, then let’s go.

Gravity Falls was a Y7-rated children’s show on Disney XD. If you’ve forgotten that fact, you wouldn’t be the first. Part of the wave of prestige cartoons of the 2010s, it was of a piece with Cartoon Network commodities like Adventure Time, Steven Universe, and Over the Garden Wall. And at times the rating — appropriate for kids aged 7 and up — felt a little low.

That’s because, just like many of its Cartoon Network cousins, Gravity Falls expertly skirted the edge of what constitutes a “kids’ show,” dealing in genuine horror and surprisingly adult themes. In fact, as his show grew darker by the day and creator Alex Hirsch was asked who exactly it was geared toward, he asserted that the target audience was himself, and he was just making something he would like.

It’s an admirable approach, and not an easy one in the world of children’s tv. The show managed it, though, redefining “kid appropriate” with rivers of blood, shrieking chimeras, and bras. But Gravity Falls‘ most impressive — and most extensive — triumph over censorship was its very adult and, honestly, traumatizing main storyline, which it hid in plain sight for almost its entire run.

Gravity Falls is all about mystery. It made a name for itself concealing clues and secrets wherever it could fit them, and for encouraging its viewers to puzzle them out.

For example, the code below, from a post-credits title card, takes three successive ciphers to crack. Hints for using the always-shifting ciphers are hidden throughout the show in backward audio clips, messages in the credits (often themselves in code), and secret keys flashed for only a few frames in the background of scenes. Gravity Falls is chock full of them.

And much like the ciphers and codes it peppered throughout, the show disguised clues to its deeper and darker elements, and it trusted its young audience to find and interpret them. In case you don’t know (if you don’t, here’s your last chance to bail) this is the essential story of Gravity Falls:

Twin brothers Stanley (Stan) and Stanford (Ford) Pines suffer a terrible falling out as teenagers. Stan is kicked out of the house, while Ford makes a name for himself as a brilliant scientist. Armed with a research grant, Ford moves to Gravity Falls, Oregon to study scientific anomalies, but he’s tricked and flattered by Bill, a demon from another dimension, into building a portal between Earth and a place called the Nightmare Realm, which is about as nice as it sounds. His partner loses his mind, and he falls further and further into insanity and paranoia.

Realizing he’s been used as a force for evil but too proud to destroy his research, Ford asks for help from Stan, who’s homeless and on the run. The two reunite for the first time in over a decade, but they immediately start fighting and Stan accidentally pushes Ford through the portal, trapping him on the other side.

Stan assumes his brother’s identity and devotes the next 30 years of his life to bringing him back. But when he finally succeeds, he also brings back Bill, as well as all of his and Ford’s old enmity. The twins continue to fight and Bill very nearly destroys the world, until Stan sacrifices himself by erasing his own mind and taking Bill down with him. It’s only with this ultimate sacrifice that the two finally reconcile.

This is, by a lot of metrics, the main story of Gravity Falls. A man who’s been told he’ll accomplish great things is tricked and flattered into nearly destroying the world… twice. And a man who’s been told he won’t amount to anything sacrifices himself to save him… twice.

But you wouldn’t know it from watching the majority of the show, because none of this actually comes to light until the 31st episode, a full three-quarters of the way through the series. Until that point, we don’t even know that Ford

exists

.

That’s because we enter the story 30 years after most of the plot’s events, about a month before Ford’s return. And we’re focalized not on Stan and Ford, but on their great niece and nephew Dipper and Mabel, two twelve-year-olds who don’t know the first thing about what’s happened.

They’ve never heard of Ford, and to them, Stanley is their Great Uncle (Grunkle) Stan, an old money-grubbing weirdo who runs a tourist trap/scam called the Mystery Shack.

And that’s how we know him, too, for much of the narrative, as the bulk of the episodes follow Dipper and Mabel and their run-ins with mermen, shrink rays, and sentient Halloween candy. Early Gravity Falls is brilliant and funny and everything you could want out of a paranormal cartoon, but it’s very much about and for kids.

Not that there’s anything wrong with that.

In fact, it’s perfect. By introducing us to the world through the eyes of two young outsiders, the show is able to withhold a huge amount of information with a deniability that comes completely naturally. It can disguise its tragedy very easily, and that’s its greatest success.

The best example of this is Stan, who’s an incredibly pitiable character. Devoting 30 years of his life to bringing back the brother who disowned him, we can see him coming to terms, as he gets older, with the fact that he’ll probably never succeed.

But we don’t realize that’s what we’re seeing, because, for the first three-quarters of the show, he’s pure comedy.

Stan runs away to Vegas and marries an animatronic gold prospector. He teaches a bear to drive. He keeps ten guns in his house in case some maniac tries to sneak in a ladder. (Keeping a ladder in the house is more dangerous than a loaded gun, you see).

Stan is hilarious, and that’s vital. A grumpy old man seen through the eyes of two twelve-year-olds, anything and everything he does can be written off as inscrutable adult stuff.

And when you can reasonably explain away your character’s actions as meaningless and comedically driven, you can get away with murder.