Mason returns as a ghost and his goal is to save Tyler from Klaus. He lures Damon into a cave and traps and tortures him. When Damon is released, he goes to tell Bonnie that Mason has returned. He tells her to reverse whatever spell she did that brings people's ghosts back. She is all for it since it will also get rid of Anna.
Elena can also see ghosts, and she spots Jeremy kissing Anna. She tells Caroline and soon later Bonnie finds out. Bonnie needs Elena's necklace to break the spell but they do not know where it is. It turns out that Anna took it. Elena convinces Anna to give up the necklace and Jeremy delivers it to Bonnie.
Lexie comes back as a ghost and locks Stefan up and tortures him with Elena there. Lexie makes Stefan feel that he has gone without human blood for years. He prey's on Elena.
Grams also comes back as a ghost to help Bonnie. They put a spell on Mason just as he finds what he was looking for. Once Mason leaves, Damon goes to Alaric for help to enter the chamber. Alaric gets in and finds cave paintings.
Bonnie completes her spell and Lexie disappears, leaving Elena alone with Stefan. Lexie charges Elena to continue on with Stefan's detox. Elena tells Stefan that he has to regain home, and she leaves him there, chained up.
Before Anna disappears, she is able to reunite with her mother Pearl. Jeremy tries to make up with Bonnie but she isn't having any of that. She said that Matt was able to let go of his very own sister, so why couldn't Jeremy let go of Anna. Jeremy leaves, and Anna and Grams destroy the necklace in the fire. They notice an interesting spark.