In the end, Elena became a vampire and killed Catherine with Staffen and Damon. Catherine later became very powerful. She is hundreds of years older than S and D. Besides, she not only drinks human blood, but also kills her vampire companions and drinks their blood. E seemed to be dead, and then she came back to life. The three of them killed K and left together.

With the help of Elena and Damon, Stefan got rid of the habit of drinking human blood. Damon and the history teacher traced John's cell phone to an apartment, but they couldn't find Elena's biological mother, isobel. Pearl met John and told him that Damon had got the invention. When Anna came home, she saw her mother packing and preparing to leave. Anna had to say goodbye to Jeremy and came back to find that the pearl had been killed by John. Isobel appeared in a bar and met a drunken history teacher.

Elena and isobel finally meet, and isobel hopes Elena will make Damon hand over the equipment invented by Gilbert and threaten her with the lives of others in the town. Damon found isobel's apartment, and isobel said that she completely followed Catherine's instructions and hoped Damon would go with her. Bonnie found Elena and took the initiative to make up. Isobel kidnapped Jeremy. John got a call from isobel. Catherine's goal is to kill all the vampires in the grave. Isobel and two others, Stefan and Damon.

Caroline is the main character in the celebration when the founder's anniversary is coming. The vampire who escaped from the cemetery is preparing a revenge plan for Mystic Falls, and decides to have a massacre when setting off fireworks. Anna tells Damon about the vampire's revenge plan. At this time, John started the vampire's destruction device, and within five minutes, the ultrasonic wave from the device made all vampires miserable. When John came home at night, Elena suddenly appeared and killed John. It turns out that she is not Elena, but Catherine.