For all the fun and insane theories — including a few of my own — that the Internet cooked up this season, Jason Blossom’s killer on Riverdale ended up being fairly innocuous. The murderer was Clifford Blossom, the victim’s father, who is probably the first or second suspect on many viewers’ minds back in January when the series began. The series has since obscured that possibility with eleven episodes of red herrings, but ultimately, the killer is the most obvious character. It was an unsatisfying reveal, although twists and turns leading up to it were as exciting as this season has been since the pilot episode.
We still do not completely understand Clifford Blossom’s motive for killing his son, but the episode did reveal a number of secrets that might provide the basis for one. The biggest bombshell comes from Betty’s father, Hal Cooper, who reveals that he had stolen the files from Sheriff Keller’s office to keep a secret buried: That the Blossoms and the Coopers aren’t the Hatfields and McCoys, they are more like the Dollangangers. Hal’s grandfather was a Blossom, the brother of Clifford’s grandfather. That means that Polly and Jason are cousins, which means the child developing inside of Polly is a product of incest, which gives the murder mystery the requisite ick factor.
That hardly seems like a motive for Jason’s murder, however. In fact, Penelope Blossom is non-plussed by the revelation because the Blossoms have been keeping the bloodline pure for generations. So why did Clifford kill his son? The most obvious reason seems to be that Jason had — by attempting to run away with Polly — rejected the family business, which as it turns out is not in the maple syrup trade but drugs. The syrup is a front, and it seems that Clifford was the supplier for the Southside Serpents. Perhaps Jason threatened to reveal that secret? Or Clifford is just a spiteful man who shot his son in the head at point blank range because Jason didn’t want to follow his father’s footsteps into a life of crime.