The Vampire Diaries episode that aired Thursday showed Stefan (Paul Wesley) reuniting with his mother Lily (Annie Wersching) and therefore turning his humanity back on.

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Caroline (Candice Accola) however fled to keep her humanity turned off!

The episode set to air this upcoming Thursday, April 23, is called Because and will focus on Stefan's plan to get Caroline's humanity flipped back on.

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On Thursday night, The CW Television Network's YouTube channel uploaded the trailer, which can be watched below.

In the trailer, Stefan reveals to Damon (Ian Somerhalder) and Elena (Nina Dobrev) his brilliant plan.

Elena did point out that their first attempt of trying to get their friend's humanity back on failed miserably since "Caroline went on a killing spree."

Stefan thinks his plan is going to work though!

"First step, convince her that my humanity is still off," Stefan says, sharing the beginning stages of his plan.

Clips of Caroline and Stefan getting cozy are seen so it appears as though Stefan will use their romantic chemistry to his advantage.

The next step is to "torture her until she breaks," which seems to include using memories of her mother Liz (Marguerite MacIntyre).

Plus, Elena pieces together that Stefan and Caroline have slept together, which Damon confirmed at the end of the trailer in hilarious fashion.

Catch The Vampire Diaries on Thursdays on The CW at 8 p.m. ET.