It's 1864. The Lockwood mansion. Katherine chooses Stefan to escort her to the Founder's Ball, and Damon watches jealously on the sidelines. Suddenly, it's present day. Stefan enters a bar to find Elena and Damon playing pool. Damon tells Stefan, "Prepare to lose" and kisses Elena. Back to 1864. "Now you know how I feel," Katherine teases. "I love you, Stefan. We'll be together again. I promise."
OMG! Don't worry, Stelena fans. It was just a nightmare. Stefan wakes up in bed with Elena. Actually, it's Katherine, who used her powers to control Stefan's dreams. That badass biyatch!
If last week's episode was full of "Twilight" references (debatable for some of you, point taken) then last night's episode was backstabbing central. Damon accuses Elena of being a backstabber, though she retorts that using Damon's own manipulative tricks against him is not backstabbing. Touché! Unfortunately, Elena and Damon's snarky repartee is cut short when Damon heads off to Aunt Jenna's BBQ with the intent of stabbing Mason with silver to prove he's a werewolf.
Speaking of werewolves, Mason lets slip to Tyler that you only become a wolf if you "trigger the curse." Try as Tyler might, he can't convince Mason to fill him in on what the trigger is, so he satisfies himself with taunting his uncle about the moonstone.
Back at Stefan's house, Katherine reads his diary and mentions his interest in werewolves. Via flashbacks featuring fabulous corsets and petticoats, we find out that werewolves, not vampires, were hunting humans in Mystic Falls in the 1860s. It was George Lockwood, a werewolf, who spearheaded the founding families in the vampire-hunting quest. Katherine repeats her claim that she returned because she loves Stefan. The two ex-lovers slowly lean in (oh no…), kiss (Oh no he didn’t!) and BOOM! Stefan stabs Katherine in the back with a vial of vervain! He chains her in the basement and tortures her with more vervain, but Kat just continues her history lesson. Back in 1864, she struck a deal with George Lockwood to rid the town of vampires; she would turn in the others, and he would arrange for her secret escape. We learn that Stefan professed his love to Katherine before he knew she was a vampire, therefore before she compelled him. According to Kat, this means their love was real.
Meanwhile, Jenna, Alaric, Mason, Damon, Elena and Caroline make for a random assortment of BBQ party guests. Mason politely says that he's heard great things about Damon, and our favorite snarky Salvatore responds, "Really? That's weird, 'cause I'm a dick." Love it! Throughout the party, Damon uses his wordplay skills to hint that he knows Mason's wolfy secret. Finally, when they're alone, Mason clears the air and offers a truce. The two shake hands, but Damon grabs a silver knife, hinting that there's more backstabbing to come. Sure enough, outside the house, Damon stabs Mason in the chest with the knife. Backstabbing, chest stabbing, same thing. Fortunately, the silver myth is just that—a myth. Mason tells Damon that they're now enemies. No kidding! Later that evening, Tyler corners Mason at the house and finds out that the curse's "trigger" is murder. If you kill someone, the curse is activated and you become a werewolf. Interesting twist!
Elena is worried that she hasn't heard from Stefan, and Caroline upsets her by saying that vampire-human couples can't work out. Somehow, the whole scenario reeks of Katherine. When Elena leaves, Caroline offers to drive her, but not before purposely popping her tire. Eventually, Elena's persistence outlasts Caroline's smarts, and Elena leaves a sulking Caroline behind with the tow truck.
When Elena arrives at Stefan's, she doesn't realize that Katherine has broken free from the chains downstairs. By drinking vervain every day, Katherine has become immune to its debilitating powers. She stabs Stefan—but she loves him, she swears!—then runs upstairs to introduce herself to Elena. Isn't it strange that it's the fourth episode this season and they're just meeting? The elusive Katherine disappears as Stefan surfaces.
At the Mystic Grill, Katherine corners Caroline in the bathroom and chastises her for failing to detain Elena. Yup, we knew Kat was behind this! Caroline apologizes to Elena and is seemingly forgiven.
After the stress of the day's events, Stefan and Elena fight about Katherine. Caroline and Damon are both eavesdropping as Elena storms out. When she's back home in her room, though, Stefan is waiting for her. Hurray Stelena! Those conniving cuties staged the whole fight, since they figured Caroline was doing Katherine's dirty work. They vow to keep up the fighting façade until they can figure out what Katherine's really after.
So what is she after? In another flashback, Katherine gives George the moonstone and threatens to kill him if anyone finds out that she escaped. Before leaving, she runs up to the Salvatores, seemingly dead, and kisses Stefan. Just as in Stefan's nightmare, she tells him, "I love you, Stefan. We'll be together again. I promise."
Who’s the biggest backstabber: Elena, Damon or Stefan? What power does the moonstone hold? Can Stelena survive the wrath of Katherine? Does Katherine really love Stefan, or does she have other
motives?

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