KATHERINE’S PAST IS REVEALED — Elena puts herself in a dangerous position as she searches for the truth about Katherine’s past and what her own future may hold. Knowing that Stefan would never agree to her plan, Elena swears Caroline to secrecy. Damon uses a new-found confidant to help him try to discover the real purpose and power of the moonstone. Jeremy and Bonnie meet Luka a new student with a surprising family history.
- Antagonists: Elijah Mikaelson and Niklaus Mikaelson (mentioned in flashbacks).
- This is the first episode in the whole series to begin with a different scene during the showing of previous episode events. The others began with Stefan narrating about needing to know Elena; this episode began with Alaric narrating about vampires and werewolves, beginning what was to be a sequence of more episodes.
- This episode shares many similarities with 500 Years of Solitude, and the milestone 100th episode could be considered a loose sequel to this episode.
- It's the third of four episodes to be named after a character, the other three being: Isobel, Rose and Klaus.
- Interestingly, three of them are women, all of whom are vampires and were lovers of Damon Salvatore at one point.
- This episode is named after Katherine's real name, Katerina— a name shared by actress Kat Graham, who plays Bonnie Bennett.
- It is revealed that Rose was the vampire who sired Katherine. This differs from the novels, in which it was Klaus who sired her. We learn in the Season Five episode, Monster's Ball that the date Katherine killed herself after Rose fed her her blood was April 6, 1492.
- 1492 was when Christopher Columbus discovered the New World. Though in Ordinary People, Rebekah insinuated that North America had been already discovered by Europeans (specifically the Vikings), though this was not recorded in most American history books.
- In the book series, Katherine is German, while in the television series, she is revealed to be Bulgarian. This history was given to Katherine because her actress, Nina Dobrev, was born there and speaks Bulgarian fluently.
- It is confirmed that Katherine had a baby before becoming a vampire and that baby continued the Petrova bloodline that ended with Elena. This was first theorized by Damon in Bloodlines.
- This episode is the fifth flashback episode in the series, and the second episode to be told from Katherine's point of view.
- Katherine offers Elena her blood so she could be turned into a vampire. However, whether she was serious about her offer to help turn Elena into a vampire or was just being facetious, knowing Elena wouldn't be interested, is unknown.
- Elena gives Katherine the book detailing the Petrova family's bloodline and history, in which there is a sketch of Katherine with her parents. This is seen at the end of the episode, when Katherine looks through the book after everyone has left.
- This is the second episode this season in which we see a little bit of Katherine's humanity as she looks at the sketch of herself and her parents. The first time was in Memory Lane.
- As of this episode, Trevor is the first character to die in an episode (Rose) and still make an appearance after being killed (in his case, in flashbacks).
- Mason Lockwood later returns as a ghost in Season Three after being killed in Plan B.
- Lexi, Anna and Vicki Donovan also make appearances this season after being killed in Season One: Vicki was killed in Haunted, Lexi was killed in 162 Candles and Anna was killed in Founder's Day. Lexi returns in The Dinner Party in a flashback, while Anna and Vicki returned in As I Lay Dying as ghosts.
- It is revealed in this episode that Klaus killed Katherine's parents as revenge for her getting away and turning herself into a vampire so her blood would be useless in breaking The Hybrid Curse.
- Petrova House (flashback)
- Mystic Falls, Virginia
- Slater - Staked; committed suicide by staking after Elijah compelled him to do so
- Katerina Petrova (past) - Hanging; killed by herself (as a witch)
Behind the Scenes
- This episode had about 3.50 million viewers in the USA, which was 0.133 million less than the previous episode.
- (with translation)
- Katerina's mother:
- English: A little more, dearest... a little more. Push... a little more. A little more, a little more. Push! It's a girl.
- Bulgarian: Още малко, скъпа... още малко. Напъвай... още малко. Още малко, още малко. Напъвай. Момиче е.
- English: A girl. Please mother... let me see her.
- Bulgarian: Момиче? Моля те, майко... позволи ми да я видя.
- Katerina's father:
- English: Woman, don't! What are you doing?
- Bulgarian: Жено, недей! Какво правиш?
- English: Let me at least hold her once... just once... at least once.
- Bulgarian: Дай ми поне веднъж да я подържа... само веднъж... поне веднъж.
- Katerina's father:
- English: Forget it... You have disgraced this family!
- Bulgarian: Позор.... Позор за нашето семейство!
- English: Father, please! No, father... No! No!
- Bulgarian: Татко, моля те! Не, татко, моля те, не. Не!
- Katerina's mother:
- English: No Katerina. It's better for her! It's better for her!
- Bulgarian: Недей, Катерина. Така е по-добре за нея, Катерина. Така е по-добре за нея.
- English: No, mother, please...
- Bulgarian: Моля те, моля те не, мама.
- Katerina's mother:
- English: Let her go... let her go, Katerina.
- Bulgarian: Остави я... остави я, Катерина.
- English: Please, Mama...
- Bulgarian: Мама, моля те.
- Elijah: "I'm a special vampire."
- Katherine: "Better you die than I."
- Rose: "Being in love with your brother's girlfriend must be difficult."
- Damon: "I'm not in love with anyone."
- Rose: "Wanna try that again?"
- Katherine: "Witches and their spells. So many ingredients. So many people to sacrifice."
- Katherine (to Elena): "He killed them. My entire family. Just to get back at me for running. Whatever you do to escape Klaus, he will get his vengeance. Your friends, your family and anyone that you've ever loved."
- Katherine: (to Stefan): I don't want my freedom, because when Klaus comes to kill us— and he will come— I'll be safe in the tomb, where no vampire will enter because they can't get out. I'll be the safest psychotic bitch in town.
- Elena (to Stefan): "It`s not just me that's in danger. It's Caroline and it's Tyler and it's Bonnie... They're all part of breaking the curse. I can't blame anyone else anymore. Because it's not because you came into town, or because you and I fell in love. That's not why everyone that I love is in danger. It's because of me. Everything is because of me."