She compels Matt to pick a fight with Tyler, intending for Tyler to kill him.
A major subplot involves Katherine's plan to trigger Tyler Lockwood's werewolf curse.
Just as the characters—and the audience—think the danger has passed, the episode ends on a massive cliffhanger:
While Caroline manages to knock Matt out to stop the fight, Katherine’s backup plan succeeds when a girl named Sarah (also compelled) attacks Tyler with a letter opener. In self-defense, Tyler accidentally kills Sarah, officially . The Final Twist