In the third season premiere, it's Elena's 18th birthday. As she searches for clues to locate Stefan, Damon tries to keep her from doing anything that might draw Klaus's attention.

Damon and Alaric reluctantly go along with Elena's new strategy to find Stefan, leading Damon into a dangerous fight with an unexpected enemy.

Stefan is reunited with a vampire (CLAIRE HOLT), from decades earlier. In a flashback to the 1920s, Stefan comes face to face with a shocking chapter from his wild past.

A frustrating new enemy pushes Damon over the brink and he lashes out in a way that will have lasting consequences. Bonnie has a strange encounter that will affect everyone.

Caroline is determined to see that Elena, Bonnie, Matt and Tyler all enjoy a traditional Senior Prank Night before the school year begins ... but the evening takes a deadly turn.

On the first day of their senior year, Elena, Caroline, Bonnie and Matt still reel from recent events. Meanwhile, Stefan continues to carry out his latest assignment from Klaus.

Preparing to celebrate the traditional Illumination Night, Mystic Falls is invaded by spirits. After a violent encounter with an angry spirit, Damon asks Bonnie for help.

Elena and Rebekah (CLAIRE HOLT) engage in a power struggle, until Rebekah finally reveals some of her family's ancient secrets and the violent past she shares with Klaus.

On the night of the Homecoming dance, Rebekah (CLAIRE HOLT) tells Elena why the evening is so important to her, leaving Elena with conflicting emotions. MY MORNING JACKET performs.

Klaus turns to violence to convince Damon and Elena that no one will be safe until he finds Stefan and gets his family back. Tyler faces consequences of his actions as a hybrid.

Elena, Bonnie and Matt surprise Caroline with a small party for her 18th birthday. Tyler refuses to go along with Klaus' latest demand.

Bonnie's recurring dreams about Klaus' coffins lead her to a reunion with her mother, Abby (PERSIA WHITE - Girlfriends), whom Bonnie hasn't seen for 15 years.

Sheriff Forbes (MARGUERITE MacINTYRE) delivers disturbing news to Alaric and Elena about a recent murder weapon, and Caroline is heartbroken when unable to stop a tragedy unfold.

Elena is invited to a formal ball at Klaus' mansion and learns of a horrifying plan that could lead to numerous deaths. Who can she trust with her new information?

When Elijah (DANIEL GILLIES) gives Damon and Stefan a dangerous ultimatum that puts Elena in danger, they turn to Alaric and Meredith (TORREY DeVITTO) for help.

The present-day murders in Mystic Falls remind Damon of a similar crime spree a century earlier. Flashing back to 1912, Damon recalls a beautiful vampire, Sage (CASSIDY FREEMAN).

Damon is surprised to learn why Sage (CASSIDY FREEMAN) has returned, and pleased when she devises an unusual method to help him figure out what Rebekah (CLAIRE HOLT) is up to.

Stefan's emotional turmoil leads him to a dangerous confrontation with Klaus and, later, to a heartbreaking moment with Elena. CLAIRE HOLT and CASPER ZAFER guest star.

Caroline is thrilled when Tyler returns to town, but Tyler soon suspects that something has been going on between Caroline and Klaus. Matt tries to keep Rebecca (CLAIRE HOLT) busy.

The 1920s Decade Dance takes a deadly turn when Damon and Stefan realize they need the help of Matt, Jeremy and Bonnie to undo a spell that could be devastating for everyone.

Klaus acts on his intentions to leave town with Elena, but finds resistance from a surprising new enemy. Damon and Stefan have a surprisingly candid conversation about the future.

In the third season finale, determined to protect his sister, Jeremy makes a decision that will change everything. Bonnie makes a secret deal that has heartbreaking consequences.