Much of Riverdale season 6 had fans utterly confused as a series of nonsensical events occurred in a place called Rivervale. The season also saw the demise of a number of main characters. It was revealed, however, in the sixth and last episode before the holiday break that Rivervale, and everything happening in it, was a parallel universe.
The two universes were expanding onto themselves, which meant events that occurred in Riverdale would eventually be mirrored in some fashion in Riverdale. It was dark and twisted, but the episode finally brought some clarity to what had been going on all along. But most interestingly, it brought back characters from seasons past.
Reggie Mantle (Original)
In the first season, Reggie was played by actor Ross Butler. But as 13 Reasons Why - a Netflix show that Butler also had a role in - grew in success, the actor could no longer star in both shows. Actor Charles Melton took over the role, and there was no mention of how or why Reggie looked different all of a sudden.
In this episode, however, the show found a funny way to bring the two together, with Butler appearing in the episode as Reggie from another universe. The pair couldn't hold back their egos, leaving Veronica to scold them like children, begging them to just get along. It was the first time the two Reggies appeared on screen at the same time in the show.
Clifford Blossom
Clifford Blossom, the cruel and greedy patriarch of the Blossom family, was poisoned in the first season in one of the more believable deaths on Riverdale, after he shot and killed his only son. In this universe, he appears for a split second, dressed as The Black Hood who is about to shoot and kill Jason.
He is stopped, however, before he can fire the gun into Jason's chest. While fans expected to see Hal Cooper, who was the real Black Hood in Riverdale, under the mask, in this twisted world it was, in fact, Clifford.
Jason Blossom
Riverdale began with the untimely death of Jason Blossom, Cheryl's twin brother. He was only ever seen in flashbacks, but in the parallel universe of Rivervale, he never died. He pops in to see if Cheryl is ready for their tennis match, much to Jughead's shock.
Jason then appears in a kidnapping scene wearing the same all-white outfit he was sporting when he was killed in Riverdale. He is hunted down by the Black Hood killer, who turns out to be his father Clifford, the person who did indeed kill him in real life.
Dilton Doiley
Dilton Doiley was responsible for bringing the game Gryphons and Gargoyles back to popularity and coaxing several students to play the obsessive and deadly game. He ended up dying because of it, found in the woods, poisoned and posed.
The character returned in this episode, playing his same self, now a science teacher at the school. He still has that same obsessive personality, but about something else now: he wants to study these universes and watch them collide. Just like in Riverdale, however, he is poisoned and doesn't get the chance to go through with his master plan.
Ethel Muggs
It's fitting that Ethel Muggs returns for this episode about a parallel universe, given that she played character stuck in one in another Netflix show, Stranger Things. Interestingly, she kills Dilton because she doesn't want him to let the two worlds implode.
Ethel hadn't been seen since the fourth season of the series when she was confronted by Jughead about videotapes she dropped off to the police. She was one character fans wanted to see come back to Riverdale, so hers was a welcome return that gave her the chance to be a heroine.
Fred Andrews (Flashbacks)
While Luke Perry, who played Fred Andrews, tragically passed away, he appeared in the episode in spirit, and in a flashback scene showing him standing in a suit as a best man in Archie's vision of his father being at his wedding.
The storyline of Archie being desperate to keep the parallel universe alive because he believed his father might come back was both scary and heart-wrenching. Nonetheless, it was a nice homage to one of the fan-favorite parent characters from the show.
Ben Button
Ben Button was one of the victims of Gryphons and Gargoyles, and one of the saddest deaths on Riverdale. He believed he needed to "ascend" just like Dilton. So, while in the hospital recovering, he ran and jumped out of a window.
In Rivervale, Jughead was washing his hands in the bathroom at the school only to look over and see Ben, clearly much older now, washing his hands at the sink beside him. Jughead is dumbfounded at how Ben could possibly still be alive, given that the scene occurs before Jughead becomes aware of the parallel universe.
Whoopee Cap Wearing Jughead
In the earlier seasons, Jughead was never seen without his signature whoopee cap. But eventually, as he got older and matured, he eventually retired it. For a split second as Jughead entered the parallel universe, he catches a quick glimpse of his old self wearing the hat, grabbing a drink at the water fountain.
A version of the hat is seen again when he arrives at the version of Pop's in the sky after dying for a short moment before reanimating. The version of the hat in that scene, however, is one straight out of the original Archie comics, perched at the side of his head. He is also wearing Jughead's comic book shirt with an "S" on the front.
Hal Cooper
Hal's death was one of the biggest character deaths on Riverdale. For so long, he appeared to be the perfect, doting dad. But then, it was discovered that not only was he secretly having an affair with Penelope Blossom, he was also a heinous serial killer terrorizing the town. He finally met his demise at the hands of Penelope after spending time in jail and coming face to face with his daughter Betty.
In Rivervale, Hal is seen in a single scene at Pop's during Betty and Archie's wedding rehearsal dinner. He says a few words to the bride and groom with a smile, right before Toni walks in to deliver the terrible news that Cheryl has been murdered.