Jason Blossom's Killer was a previously anonymous character responsible for the murder of Jason Blossom on July 11th.
Jason was thought to have drowned after an early morning boat ride with his sister Cheryl Blossom on July 4th. However, his body was discovered much later on. After an autopsy, it was soon discovered that he was shot in the head and died a week later around on July 11th. Jason was also said to have ligature marks, meaning the killer could've possibly tied him up or held him captive.
Editor's Note: The characters listed down below are those that were suspected of killing Jason Blossom within the show. The list should not include theories based upon fan speculation.
- Mustang (captured and tied up Jason)
- FP Jones (cleaned up the crime scene)
- Joaquin DeSantos (cleaned up the crime scene)
- Hal Cooper (Hal broke into Sheriff's house and teared up evidence from the murder board)
- Southside Serpents
- Penelope Blossom
- Hiram Lodge
- Hermione Lodge (Residing in New York during Jason's time of death)
- Cheryl Blossom (assisted Jason in running away and faking his death)
- Dilton Doiley (claimed the gunshot he fired on July 4th had nothing to do with Jason. He was further eliminated when it was found out that Jason died a week later)
- Geraldine Grundy (claimed to have a gun for protection)
- Polly Cooper (pregnant with Jason's children)
- Jughead Jones (cleared by the police due to falsified alibi)
- "Chapter One: The River's Edge" (mentioned)
- "Chapter Two: A Touch of Evil" (mentioned)
- "Chapter Three: Body Double" (mentioned)
- "Chapter Four: The Last Picture Show" (mentioned)
- "Chapter Five: Heart of Darkness" (mentioned)
- "Chapter Six: Faster, Pussycats! Kill! Kill!" (mentioned)
- "Chapter Seven: In a Lonely Place" (mentioned)
- "Chapter Eight: The Outsiders" (mentioned)
- "Chapter Nine: La Grande Illusion" (mentioned)
- "Chapter Ten: The Lost Weekend" (mentioned)
- "Chapter Eleven: To Riverdale and Back Again" (mentioned)
- "Chapter Twelve: Anatomy of a Murder" (revealed)
- "Chapter Thirteen: The Sweet Hereafter"
Images Provided By the Official Tumblr for the CW's Riverdale.