Elena Gilbert's doppelgänger, Katherine Pierce (Nina Dobrev), is one of the biggest villains on The Vampire Diaries, and she runs from Niklaus "Klaus" Mikaelson (Joseph Morgan) for a serious reason. Katherine has a dark history with Stefan (Paul Wesley) and Damon Salvatore (Ian Somerhalder), as she knew them in Mystic Falls in 1864. After appearing in the Gilbert home in The Vampire Diaries season 1, episode 22, "Founder's Day," she begins her tradition of pretending to be Elena. Throughout her arc, Katherine has many enemies, including Elena, whom she's envious of and wants dead, and Stefan, who doesn't appreciate her cruel nature.

As a tough and self-centered character, Katherine does what she wants and doesn't appear to be afraid of anyone or anything. However, she has been frightened of Klaus for a long time, which emphasizes their tense and difficult relationship. While there are five doppelgängers on The Vampire Diaries, Katherine is considered the most dangerous, which makes her escape from Klaus compelling.

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Katherine Ran From Klaus Because She Prevented His Plans To Break The Hybrid Curse

Katerina looking serious on The Vampire Diaires

The Vampire Diaries season 2, episode 9, "Katerina," reveals that Katherine, who was called Katerina Petrova, came across Klaus in England in 1492 when her family forced her to leave Bulgaria for giving birth to a child without being married. In this memorable flashback, Katherine proves to be just as clever and able to think as quickly as Klaus. She learns that Klaus wants to kill her as he needs a doppelgänger to break the hybrid curse that his mother, Esther (Natalie Dreyfuss), put on him. The curse would force him to remain an Original Vampire instead of being able to be part vampire and part werewolf.

Katherine saves herself by forcing Rose (Lauren Cohan) to turn her into a vampire. This is one of the most important betrayals on The Vampire Diaries and proves that while Katherine is frightened of being killed by Klaus, she uses her intelligence and escapes him. Even though she is successful, she is always insecure and worried that she will fail next time. This speaks to Klaus's power, intensity, and danger.

Klaus Killed Katherine's Family & Swore He Would Get Revenge For Her Betrayal

Klaus smiling on The Vampire Diaries

Klaus travels to Bulgaria and murders Katherine's family because he wants her to suffer. Katherine then runs from Klaus for 500 years. However, while Klaus never stops searching for different ways to achieve his goal of breaking his curse and becoming more powerful, he doesn't actually look for Katherine for this period of time. He wants to escape his harsh father,r Ansel (Llyod Owen), and he finds others to torment. Most importantly, however, Klaus likes knowing that Katherine is scared and upset, as he is just as selfish as she is and wants to be the center of attention.

Since Klaus and Katherine are TVD's best villains, it's fitting that they dance around each other for such a long time. Katherine's obsession with Klaus is ultimately her downfall, as she is often distracted by thoughts and worries about what he's going to do when he finds her. Given their backstory and the danger that every human and creature faces on The Vampire Diaries, it's understandable that Katherine feels this way, but she also wastes a lot of time being unhappy and afraid.

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