Once Damon came back, the two were turned into vampires in 1864, in the town of Mystic Falls at the age of 17, by Katerina Petrova, who both brothers loved immensely.

On March 27, 2009, The Hollywood Reporter announced that Paul Wesley had joined the cast of The Vampire Diaries as Stefan.

Carina MacKenzie of the Los Angeles Times noted that he spent "10 years as a successful but under-the-radar TV actor" but shortly after the show premiered, he was "everywhere".

MacKenzie wrote: "Last summer his face was on more than 30 "Vampire Diaries" posters at the Century City/Westfield mall alone, not to mention billboards over seemingly every major boulevard in Hollywood".

[2] In November 2011, Wesley's ex-wife Torrey DeVitto joined the cast of The Vampire Diaries in the recurring role of Dr. Meredith Fell, who is "intrigued by" Alaric Saltzman (Matt Davis).

[3][4] Stefan was described as a "beautiful young man" who turns out to be a Vampire 162 years old, who develops a "strong connection" with "tragic heroine" Elena Gilbert (Nina Dobrev).

Wesley stated: "The dynamic of the characters is so interesting because they love each other, but they hate each other [...] There's always this thing in Stefan's head where he hopes that one day Damon can just be as normal and functioning as possible".

"[2] When the original vampire Klaus Mikaelson (Joseph Morgan) is feared dead, it is revealed that everyone in his bloodline will die, including Stefan and Damon.

In what International Business Times called "the moment Vampire Diaries fans have been waiting for", Elena had to pick to say goodbye to Stefan or Damon.

The thing to remember is that Stefan and Elena have this love that is so strong, and it was sort of the core of Season 1 — you can't entirely disregard that".

[14] In 1864, Stefan "hadn't yet learned the careful control that rules his life now" and was an avid consumer of human blood, which was considered a "dark past" by Zap2it.

[2] Stefan became addicted to human blood again, but got it under control with the help of Elena, who began letting him feed off her in small amounts to build up discipline.

His humanity was taken away by Klaus, and the audience met "The Ripper", his "bloodthirsty, ruthless alter-ego who had previously only been legend" according to Zap2it, who found "this sociopath version of our hero far more compelling than his usual compassionate martyr self".

In season two, Stefan starts to take small amounts of Elena's blood each day to mitigate its effect on him and to increase his strength.

After Klaus gives Stefan his blood to save Damon from a werewolf bite, he turns into a Ripper again which he does from his brothers sake.

Stefan starts working for him as he agreed to do to save Damon, and hopes it might also protect Elena by making sure Klaus never returns to Mystic Falls, since he believes her to be dead.

In the end, Elena chooses Stefan over Damon, but when Rebekah causes Matt's truck to drive off Wickery Bridge, she is trapped underwater.

After his "bunny diet" disagrees with Elena stomach she seeks help from Damon to find an alternative blood source.

When Connor kidnaps Jeremy, April, and Matt, and keeps them hostage at the Grill, Stefan must stop Damon from rashly walking in and killing his chance at curing Elena.

When Elena begins to hallucinate because of Connor's death, Klaus informs Stefan and Damon that she must be locked away to keep from killing herself, and kidnaps her before they can say no.

Luckily, Stefan realizes that Jeremy is a potential hunter, and tells him that to save his sister, he must kill a vampire.

Jeremy kills the hybrid Chris who originally helped them free Elena, and in turn her hallucinations end, and she is safe, but only barely.

During the Miss Mystic Falls Pageant, Stefan Turns a criminal in the hospital and convinces Jeremy to kill him to make the hunter's mark on his arm grow.

In the episode 'Home' he is Resseructed because Liv did a spell due to which he and his other friends can get back but Damon and Bonnie are left there leaving everyone broken.

With Valerie's help, Stefan kills Julian, but he becomes a target of the Vampire Hunter Rayna Cruz who has eight lives.

However, with Arcadius' death, Katherine Pierce returns as the new queen of Hell and seeks to destroy Mystic Falls and get her revenge for what the Salvatores and their friends had done to her.

In the afterlife known as Peace, Stefan is reunited with Lexi Branson and, decades later, Damon after he perishes of natural causes following a long human life with Elena.

In a crossover with The Originals, Stefan seeks out Klaus' help with Rayna Cruz during The Vampire Diaries season seven's "Moonlight on the Bayou."

As a result, Stefan, Damon, Caroline and all of the other vampires descended from Klaus are no longer tied to him, meaning that they are safe if he dies.

In addition, Davina is able to use power generated by the spell to resurrect Kol Mikaelson who was killed by Jeremy and Elena years earlier during the hunt for the Cure.