This article contains spoilers – frankly, IS one big spoiler – for Game of Thrones 8.5, “The Bells”. You have been warned.

Okay, let’s get this straight. Whatever else this week’s Game of Thrones was about, it was not about a hero turning bad.

For one thing, if this show has taught us anything, it’s that there are no heroes, only protagonists: flawed people trying to do right thing, or to serve their own interests, and a lot of the time they can’t tell the difference between those motivations. The way the structure of the show has kept Jon Snow and Daenerys Targaryen on the sidelines until the final act may lead you to believe that they’re the heroes Westeros has been waiting for. But George R. R. Martin’s story has always delighted in overturning narrative conventions, and it’s not going to stop now.

So Jon Snow is pure hearted, the true heir to the throne, and, in every sense that matters, a complete fucking idiot: he makes bad calls, has never actually won a battle, and has repeatedly had to be bailed out, mostly by his sisters. But the other characters, like a chunk of the audience, want to believe in him, because they desperately want a hero to make everything better.

Daenerys, meanwhile, is a woman who has spent the last eight years developing an increasingly strong sense of her own destiny. She has repeatedly survived and prospered against the odds, leading her to believe her own propaganda, that she was born to reconquer Westeros and sit the Iron Throne. Then, at the moment she is poised to do just that, she magnanimously diverts from her path to deal with the small matter of saving the world. Of course she thinks she’s the second coming.

But Westeros doesn’t agree, and Daenerys was never really the hero, because this story doesn’t have any. Her people do not welcome her with open arms. She sees her closest advisors die, and her more recent ones fail, or betray her. Two of her dragons are dead.

And then she finds that the purpose to which she’s dedicated her life is a lie, because she’s not even the rightful heir: that title instead belonging to her lover, who also happens to be her nephew and who, even as he assures her he doesn’t want the throne, deals with this revelation by breaking up with her, leaving her feeling more isolated than ever.

Ever since she calmly watched her husband murder her brother halfway through the first season, we have always known that Dany is capable of cruelty and violence when she feels threatened, and the fact those impulses have often been aimed at bad people does not change the fact they were there. (They were also, as Samwell Tarly would tell you, not always aimed at bad people.) And by the point her armies attack King’s Landing, Daenerys is isolated, and frightened, and traumatised.

So when she doesn’t accept the city’s surrender, this is not because she’s turned bad, or evil, or whatever other adjective you want to use. All she does is lash out.

But she controls the fantasy equivalent of a nuclear weapon: when she lashes out, thousands of people die. The argument being made is not that Dany was a villain all along, because in this story, there are no villains. It’s that you shouldn’t put that much power in the hands of any one vulnerable human, because they may one day be guided by rage or fear or loneliness.

I don’t think it’s a coincidence that this episode showed us Cersei Lannister at her most vulnerable, even sympathetic, at the moment it showed Dany at her most brutal: we’re meant to realise that both have ended up as who and what they are because of the game they’ve been playing. Nor is it a coincidence that several other characters here are also motivated by revenge. The Hound is consumed by it, but warns Arya off, and she, having spent years nursing her kill list, finally grasps how destructive an impulse this is, and switches to trying to save lives rather than take them. The desire for vengeance, the story is saying, is toxic. (Jaime Lannister, whatever else you can say about him, is to the last motivated by love.)

It was clear even before it had finished airing that a lot of people hated this episode, because of its brutality, or because they think it betrayed the characters or the story. But I found it one of the most powerful, most viscerally truthful, hours of television I have ever seen. And the critics are wrong about betrayal. This was always the story the show has been telling. This is the only way it could end.