Riverdale, the CW soap that doubles as an alternate-world adaptation of Archie comics, recently wrapped its third season with a characteristic mix of utter nonsense and mic-dropping bravado. After a winding series of 22 episodes that saw some of the show’s weirdest, strongest storylines (the cult-like hold of a role-playing game called Griffins & Gargoyles; Archie’s prison break) as well as some of its most tedious, inexplicable detours (Archie’s boxing gig; endless Hiram Lodge real estate shenanigans), the season finale ended, as the show often does, with a killer teaser for what might happen next.

After the show’s sexed-up reimagining of Archie (KJ Apa), Jughead (Cole Sprouse), Veronica (Camila Mendes), and Betty (Lili Reinhart) survive a final, potentially deadly session of their Dungeons & Dragons stand-in, they gather at the local diner to make a milkshake toast to their upcoming senior year. They vow not to get mixed up in any more organ-harvesting cults or murder-mysteries, and the show intercuts a flash-forward that has Archie, Veronica, and Betty burning their bloodied clothes (blood and underwear; classic Riverdale!) and Jughead’s beanie. Jughead is conspicuously absent. As the present-day foursome promises to stay friends forever, three of their future selves are agreeing to go their separate ways and never speak again.

Based on past seasons of Riverdale, this intriguing development will probably lead into a fourth season with some wildly entertaining episodes with a noir-ish or horror-mystery tint, and plenty of strung-along plotting that barely makes sense from moment to moment, never mind episode to episode. Archie will do or say things that betray little understanding of high school’s basic mechanics. (In the third season, he seemed to think junior year curriculum would mostly be direct preparation for the SATs.) Veronica’s relationship with her father (does she want to destroy him? Go into business with him? Strike a truce?) will remain frustratingly murky. Betty will do detective work that amounts to approaching suspects and demanding that they confess. The reliable Rachel Talalay will direct a few episodes with a particularly striking use of canted angles, moody lighting, and ample fog.

The show’s erratic quality can be an asset — a more consistent Riverdale would also probably be more cautious and generic — but it can also be frustrating because there’s constantly a better show buzzing underneath that’s better able to reconcile its weirdest, boldest, most gruesome moments with less arbitrary characterization. For every Cheryl Blossom, who actor Madelaine Petsch gives such self-determination and panache that even her most outlandish behavior (like de facto grave-robbing in the finale) seems believable, there’s a Kevin Keller (Casey Cott), who’s presumably going to reintegrate into the halls of Riverdale High next year, after decamping for that organ-stealing cult and betraying some of his closest friends. The particular way Kevin has been written into a corner is the show’s shortcoming in a nutshell. Even on a stylized teen soap, it’s hard to become invested in characters who are constantly jerked around by a nonsensical master plot.

As it turns out, a movie that came out just a few weeks after the Riverdale season finale unexpectedly illustrated the tricky balance between heightened genre nuttiness and genuine characterization that Riverdale often fails to strike. Tate Taylor’s Ma is being advertised as a stalker horror movie, and it is that — to some degree. As Keith Phipps noted for The Verge, the movie is skittish about its racial politics, and Taylor doesn’t always maximize its suspense. Some of the movie’s tonal switches from comic discomfort to menace are more jarring than scary.

But one of the story’s unexpected (and almost certainly unintentional) qualities is the way its setup runs parallel to Riverdale’s world. Octavia Spencer’s title character, whose real name is Sue Ann, lives in the same underpopulated, overcast small town as many of her former high school classmates. Like the adults of Riverdale, they’ve stuck around their hometown and often had children of their own. Erica (Juliette Lewis) was an exception, until she wasn’t: the movie opens on her reluctantly returning to town with her teenage daughter Maggie (Diana Silvers).

Maggie quickly falls in with a group of popular kids who happen to ask Sue Ann to buy them booze. She agrees, and eventually becomes a sort of den mother to the group, allowing them to drink and party in her basement, with cool-mom justifications. (If they’re going to drink, she claims, she’d rather they do it where they’ll be safe.) But “Ma,” as the kids nickname her, is lonelier and less well-adjusted than she lets on. As Keith points out, the movie plays a little like a variation on Carrie; Taylor even breaks out a Brian De Palma-style split-diopter shot at one point. But though the movie’s nuttier moments are a lot of fun, they’re more effective because they’re counterpoints to characters who feel lived-in.

There’s a small moment midway through the movie that particularly resonates: Maggie is making out with her new boyfriend when she hears her mom arriving home from work. Maggie rushes off the couch and into the kitchen so she can collect herself while pretending to grab a drink while her boyfriend introduces himself. The ruse is halfway convincing, but as Erica enters the room and sizes up the situation, she quietly but deliberately picks up a couple of pillows that were knocked to the floor by the couple’s make-out session and places them back on the couch. She wants her daughter to see that she hasn’t been fooled but doesn’t want to make a scene. It’s hard to imagine Riverdale handling a similar moment without forcing a stilted, go-nowhere confrontation.

Throughout Ma, even in its bumpiest and pulpiest passages, these kinds of details come through in observable shorthand, rather than clunky exposition. The teenagers’ dialogue is believable, rather than archly heightened. On Riverdale, Veronica enters every conversation armed with a series of ’80s and ’90s pop culture references that are suspiciously similar to those a 30-something TV writer might make.

That referentiality is part of Riverdale’s DNA, and it’s not a bad thing. The Archie Comics-meets-Twin Peaks logline is irresistible, even though little about the show feels genuinely Lynchian. But seeing Ma recall horror classics (and fellow Riverdale reference points) like Carrie and Halloween underlines just how thinly conceived some of Riverdale’s homages can be. Riverdale recently broke out a direct Jawbreaker homage, an admirably deep cut that nonetheless felt redundant in a season that also featured a Heathers musical episode. If the show already went all in on Heathers, why take the time to pay separate tribute to an empty rip-off like Jawbreaker, except as a reminder that some people inexplicably consider that movie a cult classic?

Of course, Ma is just one movie. It only has to sustain its characters and sense of place for 90 minutes (or roughly the length of two Riverdale episodes). Still, seeing a genre movie that addresses class, generational conflict, and small town quirkiness with this much skillful grounding makes it harder to excuse Riverdale’s shaky sense of character. Octavia Spencer gets to do plenty of outlandish stuff in her horror vehicle without sacrificing her character’s sad internal logic. Even when Ma goes into horror mode, the movie feels like it’s working with her performance, not against all natural instincts.

On the plus side, the way Ma overcomes its own weaknesses to combine genre madness with plausible characterization provides an unlikely beacon of hope for Riverdale. Maybe a savvier, less scattershot version of the show could still emerge from the small-town fog.