As the dust settles on the wreckage of Rian Johnson's Glass Onion: A Knives Out Mystery, let's go over the ins and outs of what literally happened at the end.

We'll join the action just after the flashback following Benoit Blanc and Helen-as-Andi ends, when the Distuptors realise Duke's pistol is missing and Helen's just taken a bullet right in the diary. Blanc fakes her death with some of Jeremy Renner's patented hot sauce and hauls the rest of the gang into the Glass Onion to run down the whys and wherefores of Helen-as-Andi's apparent death.

We know by now that Andi apparently killed herself by overdose at her home. Then we get into it. Blanc concludes that Miles did all three murders – or, at least, two murders and one attempted murder – to make sure that Andi never made public the fact that Miles stole the Alpha company from her, and that she was the actual genius behind the idea which started Alpha.

She had been pushed out of Alpha because she knew how dangerous Klear, the revolutionary clean hydrogen fuel Miles had developed, really was and wanted to stop him before his recklessness killed anyone. More on which later.

That napkin would also have proved that the five Disruptors perjured themselves by backing up Miles in return for his support for their various ventures.

This, Blanc says, is because Lionel flagged up the existence of the cocktail napkin to Miles. Knowing his company was suddenly in danger of being taken away from him he popped round to her house in his one-of-a-kind Porsche, Baby Blue, and drugged her.

Unfortunately for Miles, Duke spotted him leaving Andi's house and sussed that Miles had been involved. We heard Duke sounding like he was making a slightly begging pitch for a gig at Alpha News early on in the party after learning that his viewing stats were up; it turns out he was actually blackmailing Miles having found out that Andi was dead and that Miles was likely responsible.

After killing Andi in a premeditated move, he quickly switched drinks with Duke to make sure Duke got the one with pineapple juice in. As we heard when the Disruptors and Blanc were sprayed with the Covid-repellent throat spray (by Ethan Hawke, cameo fans!), "Duke don't dance with pineapple". Duke's allergic reaction killed him, and Miles successfully convinced his mates that the 'poison' that killed Duke was meant for himself. That kept him above suspicion for a while.

preview for Glass Onion: A Knives Out Mystery - Official Trailer - (Netflix)

Meanwhile, Helen has failed to find the napkin from the Glass Onion bar despite tearing everyone's rooms apart. She realises it's in Miles' office, but as soon as she's got it and revealed who she actually is to the group, Miles burns the napkin with his absurdly powerful lighter. The Disruptors turn away from Helen, sure that Miles is still their ticket to the futures they want.

So, it's all over for Andi's legacy. Helen retaliates by pushing over one of Miles' glass sculptures. One by one his former mates join in, until they're all in an orgy of destruction to work out their impotent rage at him and at themselves for tethering themselves to him. What finally snapped their loyalty was, yes, that he killed Andi. But it was also the realisation that he didn't care about them and was using them.

Helen's final play is to destroy Miles completely. Just like her sister Andi warned, Klear is far too unstable to be used as a power source. Helen launches a nugget of Klear at the fireplace. Just as she'd noted earlier on, Kathryn Hahn's Claire realises they're in the middle of the feared "Hindenburg". (As a nod to explosive hubris, there aren't many better examples.)

The Glass Onion explodes and the gang realise that they really ought to testify against Miles. Blanc and Helen wait for the police to dock at Miles' completely useless Banksy-designed jetty. Enter the Beatles to play us out.

But of course this is a Knives Out mystery, and inevitably there's more happening here.

Why does Miles hide the napkin rather than burn it in the first place? Well, Miles is a guy who's just really bad at making plans. Klear kills him, and ensures he'll get his wish to be mentioned in the same breath as the Mona Lisa. It's just that the breath is going to be saying, "Miles Bron, the guy who destroyed the Mona Lisa with his incredibly dangerous fuel".

So he's done, forever. His mates smashing those artworks is, weirdly enough, a reaction that fits Miles' view of the world. He talks about disruption as a series of incrementally bigger transgressions and norm breakages. Eventually, they work up to destroying the one thing, as he puts it, that nobody wants destroyed: the Mona Lisa. And in consciously or unconsciously following Miles' credo, they show how useless it is.

And Miles' murders are the essence of what makes him such a charlatan. Like his Glass Onion building they look complex, but there's nothing in the middle of them. They're hack work. They are stupid, reflexive decisions dressed up as ingenious plans.

preview for Behind the Scenes of "Glass Onion: A Knives Out Mystery"

Birdy wonders aloud about Miles' plan being so dumb it's kind of genius. "No," snaps Blanc, "it's just dumb!"

The moral here is not to mistake the trappings of the super-wealthy and apparently successful for proof of their worthiness. They're just so many layers of the onion.

One hanging question: what happened to that stoner guy Derol? He's played by Noah Segan, who also turned up in Knives Out as Trooper Wagner. Could he be the missing link, the secret ally who props up Blanc? Let's wait for Knives Out 3.