Fans of "The Vampire Dairies" won't want to miss the midseason finale, "Fifty Shades of Grayson," this Thursday, which promises to be thrilling and exciting.

In the upcoming episode, the tables will be turned on Damon and Elena as Damon will realize that his girlfriend is in danger and will seek Stefan for help. The Salvatore brothers will also pay a visit to Aaron in order to help get Elena back. Plus, Damon will unveil shocking first-hand knowledge of Aaron's family to Stefan, notes WetPaint.com.

In addition, Dr. Wes is set to unleash his secret weapon after Damon and Stefan confront Aaron for help in finding Elena. In the meantime, Elena will learn more about Whitmore College's dark past and Dr. Wes' ultimate goal.

In the promo for the episode, Stefan is seen threatening Aaron's life in order to get Elena back, but Dr. Wes responds with his own threat.

Meanwhile, back in Mystic Falls, a frantic Katherine will turn to Matt for help before she realizes that only Nadia can solve her problem.

SpoilerTV released a full synopsis, which reads:

"Damon (Ian Somerhalder) realizes Elena (Nina Dobrev) is in danger and enlists Stefan's (Paul Wesley) help to find her. The brothers pay a visit to Aaron (guest star Shaun Sipos), and Damon shocks Stefan by revealing his first-hand knowledge of Aaron's family. In an attempt to stop Damon, Dr. Wes (guest star Rick Cosnett) unleashes his secret weapon, forcing Damon to deal with a part of his past he thought was gone forever, as well as the consequences of his decades-long plan for revenge. Meanwhile, Elena is horrified by Dr. Wes' confessions about the dark history of Whitmore College and his own ultimate goal. Finally, a frantic Katherine (Nina Dobrev) turns to Matt (Zach Roerig) for help, until she realizes that Nadia (guest star Olga Fonda) may be the one who can solve her problem."

Next year, TV Line's Ausiello reveals that Klaus will make a return visit to the show, sometime in early 2014. He also revealed that Katherine-Elena dynamic is about to get a lot more complicated.

The Vampire Diaries airs Thursday nights at 8 p.m. ET on The CW.

Watch preview clips below.