The 'Riverdale' Season 4, Episode 5 Promo Brings Back The "Serial Killer Gene"

If you heard a collective groan immediately following Riverdale's Oct. 30 episode, it's probably not because viewers were disappointed with the show's Halloween shenanigans. What's more likely is that fans caught a glimpse of Riverdale's Season 4, Episode 5 promo and realized they were in for a comeback of a somewhat unpopular plotline. But despite the less-than-enthusiastic response to the revival of Betty's "serial killer gene" drama, there are plenty of routes this new episode can take regarding this conflict... and let's be honest, if you're a Riverdale fan, you're going to watch it no matter what.

Warning: This post contains spoilers for Riverdale Season 4, Episode 4. In the penultimate episode of Riverdale Season 3, Betty was informed that she is a carrier of monoamine oxidase A (MAOA), otherwise known as the "serial killer gene." This super-fun conversation took place at The Farm, so many fans speculated that this was just a ploy by Edgar Evernever to manipulate Betty, but Riverdale fans should have known better to think this topic would be a one-and-done thing. On the contrary — Betty's supposed serial killer gene is the sole focus of the Season 4, Episode 5 promo, meaning it's coming back in full force for the upcoming episode.

First off, let's get this straight: MAOA is a real-life thing, and some believe it is linked with violent behavior, but the science behind is way more complicated (and controversial) than how Riverdale has portrayed it so far. Of course, a show that's about high schoolers fighting to survive against masked serial killers and organ-harvesting cult leaders can't really be expected to get into the details of a topic that might actually require a PHd to understand, but still.

It's still unclear just how in-depth the new episode will get into the serial killer gene storyline, but it does look like Charles will be involved. In fact, some fans are speculating that Betty's recently-introduced half-brother may also be a carrier of the supposed serial killer gene, which could explain some of his iffy behavior as of late.

If this storyline still isn't your jam, don't fret. The upcoming episode, titled "The Trials of Hiram and Hermione," is clearly going to explore more than just Betty's issues.

Check out the full synopsis:

Caught between Hiram (Mark Consuelos) and Hermoine’s (Marisol Nichols) double trial, Veronica (Camila Mendes) grapples with what the future holds for her family. Archie (KJ Apa) finds himself the unexpected target of the town’s local businesses. Betty (Lili Reinhart) and Kevin (Casey Cott) join the Junior FBI Training Program, and Jughead (Cole Sprouse) learns some surprising information about his family history.

Fans can catch all this on Riverdale Season 4, Episode 5, airing at 8 p.m. ET on Wednesday, Nov. 6, on The CW.