WARNING: The following article contains spoilers for "Riverdale," Chapter Thirteen: Anatomy of a Murder."


Who killed Jason Blossom? That's been the central question of "Riverdale" since the CW drama debuted in January. While the show has prompted much speculation about the murderer's identity, Thursday's episode came with a shockingly dark revelation: Clifford Blossom (played by Barclay Hope) murdered his own son.

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Showrunner Roberto Aguirre-Sacasa explained to The Hollywood Reporter how the producers arrived at that decision, saying,"When we originally pitched the season, Warner Bros. and The CW were like, 'When you come into that room to pitch the season, you'd better know who killed Jason Blossom.' What we did was I went in with three likely suspects and three reasons why. One was FP Jones [Skeet Ulrich], one was Hiram Lodge and one was Clifford Blossom. As we were working on the season, Hal Cooper [Lochlyn Munro] also became a possible suspect.

"But then sort of around halfway through the season, when we were thinking about the show and what the show was -- and the show is on some level a deconstruction of the Archie myth that everything is safe, that everyone is good, that parents protect their children," he continued, "that fundamentally the world is a good place -- it felt like the ultimate subversion to that, the darkest, most taboo thing we could do, is a parent killing a child. Once we landed on that being the point of no return, about halfway through the season, we started to build to Clifford."

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With one episode remaining in the season, Aguirre-Sacasa teased a "shocking story in the finale" for Cheryl, and a deeper explanation of what led Clifford to commit filicide, claiming that "ultimately... what happened in that barn will be knowable."

Now that the first season's main plot line has been resolved, it remains to be seen in what direction "Riverdale" will go in its second season. However, Aguirre-Sacasa indicated the series will further explore Jughead and the impact the character's tumultuous life will have on him. The showrunner also teased the possibility of Jason reappearing in later seasons. "I feel like there are strands and tentacles coming out of the Jason Blossom mystery that we'll always be playing," he said. "Is it the last time we've seen Trevor as Jason? I would say no, you might see him again."

Airing Thursdays at 9 p.m. ET/PT on The CW, "Riverdale" stars K.J. Apa as Archie Andrews, Lili Reinhart as Betty Cooper, Camila Mendes as Veronica Lodge, Cole Sprouse as Jughead Jones, Marisol Nichols as Hermione Lodge, Luke Perry as Fred Andrews, Casey Cott as Kevin Keller and Madelaine Petsch as Cheryl Blossom.