Although Caroline is in no mood to celebrate her 18th birthday, Elena, Bonnie and Matt surprise her with a small party in an unusual location. Damon and Stefan disagree on the best way to handle Klaus , and a reckless Stefan decides to test his theory by taking things to dangerous extremes. Bonnie is concerned when Elena tells her about Jeremy's new plans. At a Founder's meeting, Alaric once again runs into Dr. Fell, who is in the middle of an argument with her ex-boyfriend, the medical examiner. Tyler refuses to go along with Klaus' latest demand, and is surprised when Klaus seems to accept his decision.

Damon and Stefan try a brutal new approach to provoke Elena into turning her humanity back on, and Caroline is frustrated when her attempt to intervene backfires. When Elena figures out a way to call the Salvatore brothers' bluff, they call for backup from a surprising source. Matt gives Rebekah some unsolicited advice on her life choices, and she tries to help him in return. Caroline has a confusing and dangerous encounter with Klaus, and Katherine is suspicious when Bonnie makes her an offer that she promises will benefit them both.

After realizing the downward spiral he was on, Damon decides he’s going to turn over a new leaf and that his actions moving forward will do right by Elena. Lily prepares for the arrival of a special figure from her past, while Enzo stands by not sure what to expect.

Elsewhere, at Caroline’s urging, Stefan comes face-to-face with Valerie and learns some upsetting details about her past, while Enzo and Bonnie find themselves at odds when they’re forced to fend off a violent threat. Finally, when Bonnie learns some disturbing information involving the Phoenix stone, she is forced to confront Alaric.

When his experience in the Phoenix stone leads him to do the unthinkable, Damon finds himself without a care in the world, spiraling out of control and under the influence of a dangerous and reckless Julian. Refusing to give up on his brother, Stefan attempts to reason with Damon only to uncover the devastating reason for his descent.

Elsewhere, Caroline begins having some dangerous side effects as a result of her supernatural pregnancy and is forced to turn to Valerie for help. Meanwhile, Bonnie, Nora and Mary Louise attempt to track down a ruthless vampire hunter named Rayna after they suspect that she has reemerged.