While Season 3 focused on the death of villainous football star Bryce, audiences got to learn more about his sidekick Monty’s backstory. At the end of Season 2, viewers watched in disgust as the Liberty High footballer sexually assaulted fellow student Tyler Down with a broom handle in the boys' bathroom. 

In the latest installment in the franchise, we learn that Monty has not come to terms with his sexuality. He regularly uses homophobic language to mask his own insecurities and bullies Tyler relentlessly. Tyler comes forward as a rape victim and bravely reports his abuser to the police. Arrested on charges of sexual assault, the last time the audience sees Monty is when he is being transported to his prison cell.  

When Ani reports to Deputy Standall that Monty is Bryce’s killer, he tells her: "Montgomery De La Cruz was killed in his jail cell just hours ago.” His death is not shown on-screen; therefore, we do not know who killed him, but assume it was a fellow prisoner.

In the season finale, Monty’s partner Winston confronts Ani, telling her he knows she fabricated the story. How? Well, the two students were together on the night Bryce was killed.