Last week, "Riverdale" kicked off with the murder of Jason Blossom, Cheryl Blossom's twin brother. Jason's death will be a mystery that looms over the course of the show's first season, and the characters aren't the only ones trying to figure out who did it. As it turns out, the cast is in the dark as well. During a set visit, stars KJ Apa and Camilla Mendes offered their own theories about Jason's murder.

"Obviously, we have no idea yet, but we kind of have our different theories," shared Apa, who plays Archie Andrews. "I thought for a while it was Cheryl. I could be wrong, but I don't know! We don't know. We have absolutely no idea. We're kind of kept in the dark a little bit, and I think that's kind of beneficial for us as well in terms of the acting side of it."

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"I speculate so much!" added Mendes. "And we know that [the writers] all know, and it drives me crazy. I keep thinking my dad has something to do with it."

As to whether or not Veronica could be the killer, she said, "No! I don't think I could be, but I think my dad -- not that he necessarily did it, but I feel like he has something to do with it. But I could be wrong! Who knows? But you heard me say it, so if I'm right, it's on camera."

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Of course, Veronica's father Hiram Lodge hasn't yet arrived in "Riverdale," considering he's in legal trouble for embezzlement in New York. However, that doesn't mean he won't show up at all. Asked whether Hiram would turn up down the line, Mendes teased, "I think we are! I'm not entirely sure, but I think it's coming."

In the conclusion of "Riverdale's" pilot episode, Kevin Keller and Moose discovered Jason Blossom's body after it washed up on shore. Seeing as Cheryl told the authorities that her brother drowned in a boating accident, his body has opened up a floodgate of questions. When interviewed, both Apa and Mendes were filming episode seven, so it seems that this mystery will continue to deepen as the series goes on.

Starring K.J. Apa as Archie Andrews, “Riverdale” airs Thursdays at 9 pm on The CW. The series also stars Cole Sprouse as Jughead Jones, Camila Mendes as Veronica Lodge, Lili Reinhart as Betty Cooper, Ross Butler as Reggie Mantle and more. “Breakfast Club” alum Molly Ringwald will also recur as Archie’s mother Mary.