Jughead declares that there’s a serial killer in the town of Riverdale. At the library, he picks out a stack of books about serial killers.
Mayor McCoy puts up posters for an emergency town hall meeting. The River Vixens are shown walking home in a group. Hal adds an extra lock to the Cooper family door, while Alice writes on her computer. A package at the Blue and Gold offices is addressed to Betty. Archie practices shooting his gun in a field.
Veronica’s parents ask about the video Archie put online. Hermione declares that Veronica can no longer date Archie, but Veronica denies her and leaves. Hiram remarks that the town is ascending into chaos and confusion.
Alice and Hal confront Betty about Polly running away. Alice begins crying, saying that she’s terrified for Betty’s safety.
Fred asks Archie about the video. He argues that the video now makes Archie a target, and asks him to take it down. Archie says that the original post of the video is down, but it keeps spreading regardless.
Jughead enters lunch at Southside High, and sees Toni and the Serpents watching Archie’s video.
Betty finds the package addressed to her.
Jughead confronts the Serpents about Archie’s video. He is introduced to Fangs Fogarty, who is tasked with bringing Archie’s head in as part of an initiation into the Serpents. Jughead reveals that he knows Archie, and that he isn’t really a target. He suggests that the Serpents go after the Black Hood themselves.
Veronica tells Archie that her parents want her to break up with him. He asks for her support, and then reveals that Hiram suggested he make the video in the first place. Archie is called to the principals office.
Weatherbee confronts Archie about the threats he made in the video. He dissolves the football team until Archie disbands the Red Circle and writes a letter apologizing to the town.
Betty shows Kevin the letter from the Black Hood, saying that his killings are inspired by Betty.
The letter says that the Hood was inspired by Betty’s words at the Jubilee. The letter also includes a cipher hinting at his next target – that only Betty can solve. Betty suggests hiding the letter from everyone, but giving the cipher to Keller.
Betty shows the cipher to Alice, who then shares it with Keller. Alice reveals that she published the cipher, so that everyone can solve it.
Reggie confronts Archie for what happened with the football team. He asks Archie to sign the letter, but Archie refuses to back down. He suggests going to the South Side to make their presence known. Reggie and the football players decline, and Dilton offers to help Archie.
Veronica asks Hiram about the conversation he had with Archie. Hiram swears that he doesn’t remember, and Veronica leaves.
Toni walks in on Jughead researching serial killers. They bond over their love of true crime, and decide to help crack the cipher together.
Betty tries to crack the code. She gets a text from Jughead, offering to talk tomorrow.
Veronica arrives to the Andrews house and kisses Archie. She apologizes for accusing him earlier, and offers to support him. He reveals that the Red Circle disbanded, and she offers to help him.
Archie arrives at the Army supply store that Dilton recommended. He buys hunting gear.
Betty shows up at Jughead’s trailer, suggesting they crack the cipher together. He reveals that he already started working on it with Toni. She suggests that the whole group work together on the code.
The next day at school, Veronica shows off her red circle t-shirt. Archie gets hesitant that she’ll be caught by Weatherbee, but Veronica reveals that the Vixens are pbading out shirts.
Betty, Jughead, Toni, and Kevin try to crack the code. Betty brings up the Black Hood’s potential ties to the South Side, which Toni calls her out on. She suggests that Betty hates the Serpents, but she denies it. Toni reveals that Jughead hangs out with the Serpents at school, then leaves.
Archie spray paints a red circle on buildings throughout the South Side. Sweet Pea and the other Serpents accost Archie and convince him to leave. Sweet Pea pulls a knife on Archie, but Archie pulls out his gun.
Betty and Jughead wake up the next morning. Betty frantically leaves, making sure that Alice isn’t upset with her.
Weatherbee and Keller ask to speak to Archie. They ask him about the gun last night, and ask to search his locker. Archie opens it, and they find a black hood inside it.
Archie tells Fred that the hood was Reggie’s. Fred gets upset, and reveals that Archie scares him more than the Black Hood does. Fred leaves to attend the town hall.
Hermione asks Veronica is she really trusts Archie’s innocence, or if she’s just being blindly loyal.
Jughead returns some of Betty’s notebooks, and reveals that he read the letter from the Black Hood. He asks why she didn’t tell him, and Betty reveals that she’s scared by what the Black Hood wrote. She worries that Archie will be upset with him, but Jughead tries to encourage her. Betty suddenly gets an idea for how to crack the code.
Archie calls Veronica in the middle of the night, asking her to get something. She arrives at the school, and takes a gun out of the back of one of the school’s toilets.
Veronica confronts Archie about the gun. He reveals that he bought it because he’s deliberately tempting the Black Hood, so he can kill him. Veronica reveals that she threw the gun in Sweetwater River. Reggie and the football team arrive with pizza.
Mayor McCoy holds the town hall.
Reggie commends Archie for not ratting him out to Keller, and offers for them to rejoin the Red Circle. Suddenly, Sweet Pea and the other Serpents arrive at Archie’s door.
Sweet Pea wants to fight Archie. Archie agrees, but Veronica asks for them not to use any weapons.
Betty and Jughead find a book that she used to check out at the library – a Nancy Drew code book.
Keller rebadures the town hall that the town is safe, but Alice brings up the Serpents being the real problem. She suggests closing down Southside High and spending that money on the police department instead.
Betty cracks the code. It says “I will strike next where it all began.” – meaning the town hall. Betty and Jughead run there.
Veronica paces back and forth as Archie and the Serpents fight in the rain outside.
Fred and Alice argue about the Serpents.
Archie punches Sweet Pea in the face, and the two groups begin fighting.
Hiram tells Hermione that Fred’s argument will ultimately help their cause, because people in the town like him so much.
Betty and Jughead run into the town hall, warning everyone about the Black Hood. No one listens, but Betty pulls the fire alarm and gets everyone to leave.
Dilton gets stabbed by one of the Serpents. Archie tries to help him, and gets beaten by Sweet Pea. Veronica stops the proceedings by firing off Archie’s gun into the air.
Reggie drives Dilton to the hospital.
Betty shows the parents the letter from the Black Hood.
Veronica tends to Archie’s wounds. She apologizes for lying about the gun, and Archie wonders what he would’ve done if he’d had it. Veronica rebadures Archie that he isn’t a killer, and the two of them begin kissing. Veronica pauses, realizing there’s one thing they need to do.
They throw the gun in Sweetwater River. Jughead says that that night was a turning point for Riverdale, as it became “The town that dreaded sundown”.
Betty gets a phone call from an unknown number. She answers it, and a modulated voice introduces himself as the Black Hood.