the chaos really begins after blanc easily solves the fake murder case duke suddenly collapses and dies after drinking from miles glass as the lights go out in the glass onion the group suspects andi of trying to murder miles and they scatterwhen blanc finds helen still pretending to be andi he quizzes her on if shes found any evidence of who could have killed andi and now duke too but while theyre speaking helen is shot by a mystery assailant the bullet is blocked by andis notebook but everyone believes shes dead as blanc helps her fake her deathwhile everyone is distracted helen goes to the glass onion to try and find some hard evidence she finds the napkin stolen from her sister in miles office all the while blanc gathers the rest of the group in the art room where miles has placed the mona lisa on loan from the louvre and concludes the billionaire must be responsible for the murderblanc remembers a clue that duke had given about seeing miles driving from andis house duke found out andi had died after news broke online that the real andi had died hes got a google alert for everyone and he tried to blackmail miles with the information in reaction the billionaire poisoned him with pineapple juice which duke was allergic to miles then used dukes gun to shoot helenhelen arrives and brandishes the napkin shes found threatening to go to the police with the evidence the results would be catastrophic for everyone as they all backed up miles version of events in court that he came up with the initial idea that launched alpha but miles sets the napkin alight and the group refuses to back helen up left with no other option she sets about destroying his priceless sculptures before using klear to create a bomb that destroys the glass onion and the mona lisa with it as the police arrive the rest of the group finally turns on miles who it seems is in a whole lot of troublewho was the murderer in glass onion and what was their motiveimage credit netflixif you paid attention to our plot summary above youll know that miles is the murderer edward nortons eccentric billionaire killed both andi and duke to try and protect his secrets coming out and attempted to murder helen too after he ousted andi from alpha he went through a trial to prove he was the one behind the companys creation when andi finds evidence to dispute this miles decides there is no way out of the situation other than murdering her he goes to her house and spikes her drink before leaving her in her car while the engine is running staging the whole thing as a suicideduke was the only one who knew miles was ever at andis house as he saw him speeding away when he was on his way there after learning about andis death thanks to