|“||Samantha, don't be a gossip!||”|
— Marianna to Samantha Gilbert in 1912 (flashback)
Marianna Lockwood was a character who appeared in the sixteenth episode of the third season of The Vampire Diaries. She was from the Lockwood family line, making her an ancestor of the main character, Tyler Lockwood. She was also best friends with Samantha Gilbert.
Marianna Lockwood was a member of the Lockwood Family.
In 1912, Marianna lived in Mystic Falls and was best friends with Samantha Gilbert. Sometime later she was killed by Stefan Salvatore, who had become a Ripper after drinking human blood for the first time in decades. At the time, she was probably thought to be another victim of the "Mystic Falls serial killer," who had been murdering other members of the Founder's Council. Ten years after her death, her friend Samantha confessed to the murders as a result of her psyche being corrupted by the effects of the Gilbert ring, which, when worn, will resurrect humans from a supernatural death, after dying numerous times. The town assumed Samantha was crazy as a result of murdering her fellow Founding Family members and subsequently locked her up in an mental institution, where she remained for the rest of her life.
- 1912 (Flashback)
- Dead Man on Campus (Mentioned)
- Marianna is from Slavic descent and is a very popular feminine name. It means "bitter" or "grace". 
- Lockwood is English and means "enclosure forest". 
- Marianna was most likely an untriggered werewolf:
- She was a member of the Founder's Council due to the fact that she was born into one of the Founding Families.
- She was unable to identify Stefan Salvatore as a vampire, something werewolves are known to do, and she didn't have the strength to fight against him when he fed on her.
- Sage suggested that Damon feed on "innocent" girls, like Marianna or Samantha, which indicated that she hadn't killed anyone before, something that would be necessary to trigger her curse. However, it is possible that Sage simply made an incorrect assumption about it, though the aforementioned reasons suggest otherwise.
- At first it was thought she was Johnathan Gilbert's daughter-in law leading her to be Samantha Gilbert's mother since her wiki page first said her name was "Marianna Gilbert", not Lockwood, and listed Johnathan Gilbert as her father.
- When Stefan killed her, he shows his regrets for killing her, as he tried to put her head back after he decapitated her.
- With The Other Side's collapse, she either found peace or went to Hell.
- Marianna: (to Stefan) "I'm sorry for your loss, Mr. Salvatore. I'm told you're a distant cousin of Zachariah?"
- Marianna: (to Stefan) "Lockwood. Marianna Lockwood. And this is my friend, Samantha... Samantha Gilbert."
- Marianna: "Samantha, don't be a gossip! Shame on you."
- -- 1912