After Luke Perry died, his family got very involved in the making of the Season 4 premiere, which paid tribute to his character Fred. One way they did that was by providing the photos of Fred that Mary looks through.

The same day that Sprouse's casting was announced, Archie Comics also announced that Jughead is asexual in one iteration of the comic books. Sprouse told Glamour he had hoped he could portray the character that same way on Riverdale. He said:

I think, in this show, he's not aromantic and not asexual. I argued in the beginning, creatively, that he should be both, but in this show, he's kind of a tortured youth that ends up finding a comfort and a resonance with another person who's going through a lot of trauma. But I think that kind of asexual and aromantic representation is really important.

This is one of those instances when there was just as much Riverdale drama happening off-screen as there was on-screen. In the Season 1 finale, Apa's character Archie punches through ice to save Cheryl. But Apa got a little too into the action. Aguirre-Sacasa explained, "The second we knew that Archie was going to be punching through ice, I literally said, 'Now guys, KJ is such a committed actor, he's so method, he's so in this character and passionate, you have to make sure he doesn't hurt this hand.' So when at the end of that day I got a phone call that KJ had maybe broken his hand, I was like 'Yup.'"

Speaking of Cheryl nearly drowning, Petsch actually has a really hard time performing in scenes that involve Cheryl in water. "I'm afraid of open bodies of water. I was in a glass-bottomed boat that broke a long time ago, so I've always been kind of freaked out," Petsch told Glamour.

After Mendes auditioned, she "unable to sleep" because she was so nervous about the rigorous audition process. "I was starting to accept the fact that I didn’t get it. Finally, they were like, 'Look, there was a lot of disagreement over who Veronica should be,'" she explained to Collider. But now that Mendes is Veronica, can you even picture anyone else in her (very fancy) shoes?

Betty and Cheryl are really close in real life! Petsch told Glamour that after the two met in an airport, they moved in together and got super close as roommates. "We live together, so we can talk about my relationships or personal lives or whatever, and I feel like she’s always got my back," she said during Season 1.

The two actors attended college at New York University at the same time, although they admittedly were not friends back in their college days. At least they've gotten the chance to get closer now, thanks to Riverdale.

It's no secret that both Archie and Reggie love to work out, but it's a little-known-fact that the actors who play those characters love to do those work-outs together.

Usually TV sets will keep doubles or triples of props or costumes that get used a lot. However, Jughead's been wearing the same beanie since the beginning of the show.

Apa isn't actually a redhead, so he dyes his hair for the show. However, before he was cast, the team did try to find someone with naturally ginger locks. "I think we literally saw every redheaded young guy in L.A. It certainly felt that way," Aguirre-Sacasa told Vulture. None of the real redheads fit the bill, so luckily Apa was willing to change his hair color.

The Pop's set is located near a major industrial thoroughfare and it looks so much like a real diner that a group of truck drivers once tried to eat there.

He told Vulture, "Now there’s a Riverdale universe that’s gonna take off in print form now, too. Roberto has talked to me about writing a couple of those, which would be awesome. I’d love to try my hand at that."

She told Glamour she was originally brought in to read for Betty, but the casting director already knew she would make a perfect Cheryl.

The producers originally envisioned Sprouse as Archie, but the actor was much more drawn to Jughead's outsider status, and so he asked to audition for his role instead.

Even if Archie's music career isn't taking off, Apa has no trouble with music in real life. Apa is a talented guitarist, and it's really him playing the instrument on the show.

She revealed to Glamour in 2017 that the guy who plays Archie is the number-one cutie on the show.

Petsch said, "Archie Comics sent me vintage Cheryl Blossom comics, so I have a bunch of beautiful ones. They also send me all the covers they have now of the new Archie. I've got a crazy amount of them. And every time my mom goes to the supermarket, she'll turn all the pages to the back of Riverdale and leave them on the supermarket shelf — or she’ll buy them all — so I have so many Archie Comics!"

Apa told Vulture in 2017 that he ships Archie and Betty and hopes that they end up together at the end of the series. I wonder if his feelings have changed since then...

Murray, who plays Josie, was in heavy debt and was about to quit acting to try to earn more money right before she auditioned for Riverdale. She told Collider, "I was just about to take a break from acting for about six months, until I could get myself back on my feet financially, and then hit the ground running. This was my last audition." Good thing she made it to that last audition, because it changed everything for her.

Originally, a producer wanted to make Riverdale a time-travel movie starring Louis C.K. as Archie. Luckily, Aguirre-Sacasa was not into that idea, and fans got the Riverdale they now know and love.

Season 4 of Riverdale continues on Wednesday, Oct. 23, at 8.pm. on The CW.