We only given us so many clues as to the identity of the Lonely Highway killer on Riverdale. Yes, it's very possible that it could be Betty's FBI agent partner, Glen, who is behind everything — he's shady in the way all men who enter Betty's life are, and, much like her brother Charles, he's also a blonde FBI agent who wormed his way into her world. However, while we're analyzing whether Glen could be behind the murders plaguing Betty upon her Riverdale return, maybe we should look to another potentially obvious suspect: Polly, Betty's missing sister, who may not be missing at all.

Season 5's "Destroyer" wants us to believe that Polly is dead. Betty's older sister has been missing for weeks, and the last time we saw her on camera, she was running from a truck with a creepy skeleton on the front. However, in "Destroyer," Betty discovered that blood found on a crushed phone booth, where Polly presumably called her mom and sister from, matched Polly's rare blood type. It certainly seems like Polly is the victim of something nefarious here, but this is Riverdale, where nothing is ever exactly as it seems. Polly also has quite the history of playing both sides.

Earlier in the season, Betty learned that her sister was doing drugs with the Ghoulies, a gang that had taken over Archie's house. Polly wasn't thrilled when Betty busted in on the gang, nor when Betty criticized Polly for hooking up with truckers off the Lonely Highway (presumably for money) and leaving her twins alone with Alice for days on end. Polly reminded Betty that she doesn't have a right to judge her life in Riverdale when Betty hasn't come home in years, and Polly delivering this truth just before disappearing has made the FBI agent all the more heartbroken over the situation.

Yet while Betty is busy blaming herself over Polly's disappearance and possible death, Riverdale fans should remember something pretty important about Polly: She's hardly a reliable figure.

This is the same Polly who not only joined a cult — Edgar Evernever's "The Farm" for those who can only keep track of so much Riverdale chaos at a time — and within that cult, manipulated her own sister into believing that she was a monster and a potential serial killer like their dad. Polly dressed up like Betty, drugged her, and tried to convince Betty that she drowned their family cat. (The truth is, Betty did kill the cat, but it as a mercy killing at the behest of her father Hal and not anything like Polly described.)

Yes, Polly was in an extremely vulnerable place when she joined the cult. She was a new mother whose beloved boyfriend was murdered. She had no direction and needed some stability, even if it did come from an organ-snatching monster.

Still, we know that Polly has this need to find acceptance and belonging within her — and isn't it possible that she's falling into yet another trap here? It's possible that just like the Ghoulies destroyed Archie's house (seemingly at the behest of Hiram Lodge, who wants to devalue all the properties in Riverdale) Polly is part of a scheme to make Riverdale look like an awful place no one would want to live. Maybe she's pretending to be kidnapped in order to cash in a big paycheck from Hiram — something she'll use to finally get out of Riverdale and start a new life with her kids. Or, maybe, she's working with the Ghoulies and needs to pretend to be "missing" so that she can get into some shady business of her own, like running drugs or doing something else illegal.

Then there's the idea that maybe Polly knows about the "Mothman" conspiracy and is trying to make it seem like she was abducted by aliens. When Alice was describing her phone call with Polly, she said that Polly made it sound like she was in a spaceship. Could Polly be faking an alien abduction for some sort of monetary gain, knowing Riverdale's lore?

Right now, there are a lot of loose threads with Polly's disappearance. While I'm definitely convinced Polly is still alive (to paraphrase Taylor Swift, no body, no crime in Riverdale) I'm also not so sure she's a victim of anything here.

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