Klaus and Elijah will square off with Eva Sinclair in order to save their sister Rebekah in Monday's all-new episode of "The Originals."

In the previous episode, Dahlia, a power-hungry and vengeful witch played by actress Claudia Black, was introduced to the show and proved to be a serious threat. Fans also learned about Freya's history with Dahlia. Meanwhile, Eva Sinclair, a notorious and evil witch, regained control of her own body, leaving Rebekah trapped and powerless.

A sneak peek of the next episode, "Exquisite Corpse," reveals that Klaus will be forced to trust Freya if he wants to save Rebekah's life.

"You said that you could put Rebekah back in her original body. Do it," Klaus said.

"So you've come to your senses," Freya responded.

"My senses have not faltered, they still demand that you are not to be trusted, however circumstances dictates otherwise for now," he replied.

In the meantime, Elijah and Hayley will discover more details from Eva's past in their quest to rescue Rebekah. The synopsis also teases that Marcel will do all he can to defeat Eva by turning to Vincent for help.

According to Carter Matt, The CW released the full synopsis for this installment, which reads as follows:

"When Eva Sinclair's (guest star Maisie Richardson-Sellers) reemergence leaves Rebekah trapped and helpless, Klaus (Joseph Morgan) is forced to put aside his mistrust for Freya (guest star Riley Voelkel) in order to save Rebekah's life. Meanwhile, Hayley (Phoebe Tonkin) and Elijah (Daniel Gillies) learn more about Eva's violent past from Josephine (guest star Meg Foster), who then makes a startling revelation about Hayley's future. With time running out to save Rebekah, Marcel (Charles Michael Davis) turns to a reluctant Vincent (Yusuf Gatewood) for his help to take down Eva, but his plan takes an unexpected turn, as Eva will not go down without a fight."

Season 2, Episode 17 of "The Originals," "Exquisite Corpse," will premiere on Monday, April 6, on The CW.

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