Warning. Spoilers ahead.

Well, the Riverdale 100th episode answered so many questions — but also created new ones! For example, how did Ross Butler end up back in his role as Reggie?

As fans know, the first five episodes of season 6 have taken place in a, sort of, alternate universe called Rivervale. The Tuesday, December 14, episode of the show wrapped up the cast’s time in Rivervale and returned them back to Riverdale for the rest of the season — which is set to premiere in March 2022.

The 100th episode celebration had fans’ favorite cast members: Lili Reinhart (Betty Cooper), Camila Mendes (Veronica Lodge), Madelaine Petsch (Cheryl Blossom), Cole Sprouse (Jughead Jones) and KJ Apa (Archie Andrews). But the show also surprisingly welcomed some old cast members who reprised their roles. Ross, who departed the show after season 1, stood next to Charles Melton as they both played Reggie Mantle. Cheryl’s brother Jason Blossom (Trevor Stines) is alive and well, as is their dad, Clifford Blossom (Barclay Hope). Dilton Doiley (Major Curda), Ethel Muggs (Shannon Purser) and Ben Button (Moses Thiessen) — who all died in past seasons — were also back for the milestone episode.

“I know it can be a bit confusing, but I think it does a really, really good job of speaking directly to the audience who has stuck with us for a while,” Cole told Entertainment Tonight ahead of the episode’s premiere. “And also, it’s one of the first times — outside general narration — but one of the first times the show has actually discussed why it is the way it is, which I think is important, because this is a cult program, right? It’s really campy, it’s really large, it can be abstract at times.”

The Suite Life of Zack and Cody alum added, “It’s not exactly the most normal thing ever, but I think this episode does a really awesome job of going, ‘Oh, this is why,’ and finally letting the audience know why — that the show is not stumbling into these narratives blindly, but very consciously putting these things on paper and reacting to that paper in a very specific way. So, I think this episode is awesome. I think it does a really good job.”

So, how did Riverdale travel back in time and, essentially, bring some of their dead characters back to life? Well, Jughead had all the answers.

Scroll through our gallery for a breakdown of the Riverdale 100th episode, and what to expect when the show returns. 

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