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    9 Interesting Theories About Who The "Riverdale" Murderer Is

    *Erects a murder wall to rival Sheriff Keller's*

    The most important question for Riverdale fans right now is not whether Archie will end up with Betty or Veronica, or even whether Jughead will ever discover his true love (hamburgers); it’s who the hell killed Jason Blossom?


    Here’s what we know so far:

    * Jason had some kind of relationship with Betty’s sister Polly, which ended in a messy way. Polly ended up in a group home, apparently having had some sort of a breakdown.

    * Jason wanted to leave Riverdale forever, in a way that would ensure his parents would never find him. So his twin sister Cheryl helped him stage his own death at Sweetwater River on July 4. They said goodbye on the Greendale side of the river, and Cheryl expected to hear from Jason within a month.

    * Jason was killed around July 11. He’d been tied up, tortured, shot in the head and, at some point, frozen. His body somehow ended up back at Sweetwater River months later.

    * Archie and Miss Grundy were at Sweetwater River at dawn on July 4, as were Dilton Doiley and his scout group. Doiley shot a gun that morning, which Archie, Grundy, Cheryl, and Jason all heard. Doiley later found Cheryl after she had staged Jason’s drowning.

    So who actually killed Jason? Let’s take a look at the suspects…

    1. Alice Cooper


    Betty's mother is cold, calculating, and incredibly intense. She's hung up on Polly's "ruin" and hates pretty much everyone in town, but no one more so than Jason and the whole Blossom family. She blames Jason for what happened to Polly, so she definitely had the motive to kill and torture him — she even talked about how much she hoped he'd suffered before he died in Episode 1. But it seems just a little too obvious, doesn't it?

    2. Hal Cooper


    We haven't seen much of Hal at all on Riverdale — he's been in a couple of scenes with Alice, who is as outspoken as he is quiet. But it's always the quiet ones you've got to watch. Just because we haven't heard his anger in the way we've heard Alice's doesn't mean it's not there — in fact, he has more reason to be angry because of the way Jason and Polly's relationship affected not just his daughter but also his wife. Hal as the killer may be less obvious at this stage, but if we're playing the long game it actually makes him a more likely suspect than his wife.

    3. Betty Cooper


    Sweet Betty's dark side is unleashed when she feels protective of Polly. When Cheryl questions Betty about her sister, Betty threatens to kill her. Later, when Betty is helping Veronica get revenge on Chuck, she starts referring to herself as Polly and Chuck as Jason, nearly boiling Chuck alive in Ethel's jacuzzi. The next day she dismisses the incident, barely seeming to remember it. The show is clearly hinting at Betty's mental instability and her distress over what happened to Polly, but to be honest it's pretty unlikely one of the core four is actually the murderer.

    4. Polly Cooper

    We haven't seen Polly onscreen yet, but there's no doubt she's central to whatever happened to Jason (even if it's just as a red herring). Everyone keeps talking about her breakdown, and Cheryl seems to believe Polly had something to do with Jason's death. But perhaps she didn't have a breakdown at all, and is really pregnant with Jason's child — the fact that Alice won't let Betty see her sister definitely points in that direction. Does that make it more or less likely that Polly murdered Jason? The answer would hinge on whether she and Jason were in love or whether he really was a douche (or worse) to her. While her name was in Chuck's disgusting scorebook alongside Jason's, it has to be significant that he had points deducted for "feelings". I think there's way more to the Polly story than we've seen so far — and it's unlikely she's the killer.

    5. Clifford and Penelope Blossom


    Jason wanted to escape his parents for a reason. Did he want to run away and be with (pregnant?) Polly, and his parents murdered him out of some perverse sense of pride or possessiveness? Were they abusive? Did they discover Jason and Cheryl engaging in TWINCEST? Are they part of some kind of weird cult Jason was trying to escape? No matter what, they are shady AF and I wouldn't be surprised if they were involved somehow.

    6. Cheryl Blossom


    Cheryl has lied about what happened to Jason before — how do we know she's not still lying? Maybe Jason was really going to run off with Polly, and Cheryl tortured/murdered him in a jealous rage. There's no doubt she's manipulative, smart, deceitful, and at least a little bit evil. It'd be a fun twist, but I think it's more likely she truly loved her brother and is telling the truth about her plan to help him escape.

    7. Ethel Muggs


    Ethel has only been in one episode so far, but she made quite an impact — not least because she's played by the wonderful Shannon Purser, aka Barb from Stranger Things. Ethel was a girl-powered victim-cum-avenger in Episode 3, but there is a fan theory that she actually had something to do with Jason's murder, and it's tied to Chuck's scorebook. She did seem to enjoy Dark Betty's near-torture of Chuck a bit much. But while I wouldn't say definitively that Ethel isn't the murderer, it'd be a pretty weak resolution to the mystery.

    8. Miss Grundy

    CW / Via ~

    This woman is trouble. She may have left Riverdale at the end of Episode 4, but something tells me that's not the last we've seen of her. Did you see the creepy look she gave those random teens at the end? She is a predator. We know she used and abused Archie via his ~music lessons~, and we know she had ~music lessons~ with Jason the previous year. There has been a lot of references to the way Archie is taking Jason's place at Riverdale — perhaps he also took his place with Miss Grundy. She was there the day Jason disappeared, after all. She definitely isn't innocent, but I'm not sure she's guilty of murder (well, Jason's at least. WHAT HAPPENED TO THE ORIGINAL GERALDINE GRUNDY, HMMM?).

    9. Someone who thought Jason was Archie


    Speaking of the connections between Archie and Jason — some fans are speculating that whoever killed Jason actually meant to kill Archie. Maybe Miss Grundy, or another one of her lovers? Maybe Alice Cooper, who seems to hate Archie as much as Jason? This theory is fun but it's pretty out there. He might be a bit of a pain sometimes, but I don't think there's anyone who seriously wants Archie dead. I could be wrong, but I don't think it's super likely.

    1. Who do you think killed Jason?

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    Who do you think killed Jason?
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      Alice Cooper
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      Hal Cooper
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      Betty Cooper
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      Polly Cooper
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      The Blossom parents
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      Cheryl Blossom
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      Ethel Muggs
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      Miss Grundy
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      Someone who was after Archie
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      I have another theory (and will share it in the comments)

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