The Immortality Spell is an extremely powerful spell used to transform a mortal person into one of two immortal creatures, either a true Immortal, or an Original Vampire. The original spell was created by one of the world's most powerful witches, Qetsiyah. However, after Silas manipulated Qetsiyah into creating a spell for immortality, he betrayed her by giving the elixir to his true love Amara, both becoming the world's first and only true Immortals. Approximately one thousand years later, another powerful witch named Esther modified Qetsiyah's original spell as a solution to protect her family from werewolves and other harm. However, after she cast the spell, the Spirits retaliated against her, and she unknowingly transformed them into the first vampires.
Over two thousand years ago during the time of 1st century BC (the Biblical Times), a young and very powerful warlock named Silas fell deeply in love with a young and beautiful girl named Amara. However, because of her status as a poor girl who was a handmaiden and his status as a wealthy boy who was a nobleman, their love was forbidden due to their different social statuses. As a result, they had kept their relationship a secret out of fear that society would shun them. While the details of their relationship remain unknown, it is known that the two loved each other very much and wanted to be together for all of eternity. Determined to spend the rest of forever with his true love Amara, Silas tricked his best friend Qetsiyah into helping him create a spell for immortality. Despite their friendship, Silas knew that Qetsiyah also strongly loved him, and prayed off of Qetsiyah's love for him by asking for her hand in marriage, leading her to believe that he loved her and that the immortality spell was for the two of them to share on their wedding night. After Qetsiyah and Silas successfully created an elixir that would grant immortality to whomever drank the potion, she was later appalled to discover that Silas ran off with the elixir, giving it to his forbidden lover Amara instead. Fueled with hatred and rage, Qetsiyah created a cure for immortality along with a supernatural purgatory, known as The Other Side. Knowing that Silas could no longer die, she tricked him into believing that she killed his lover Amara, so that he would take the cure and pass away, thinking he would be reunited with Amara in death, but would actually be trapped in limbo with her.
The Original Family, also known as the Mikaelson Family, were a large family of witches who became the world's second generation of immortal creatures, and the first generation of their kind as vampires. Compared to Silas and Amara, the Original Vampires have vastly different characteristics. The most noticeable difference between the two species of vampire, are their abilities. While both species have psychic abilities, the Originals also have super-human physical abilities, e.g. strength, speed, senses etc, whereas true immortals are only slightly superior to hunters of the Brotherhood of the Five, and slightly below werewolves in human form, although their psychic and mental powers are far more superior, capable of compelling masses at once without eye contact and capable of compelling anything but members of The Five.
The parents of the Original family are Esther and her husband Mikael. Esther and Mikael had their first child in Europe, but eventually "lost" her to a plague that struck their homeland. Fearing for the lives of their future children, the two relocated to the New World with Esther's mentor and close friend, Ayana, where they had more children. Their names are, from oldest to youngest; Finn, Elijah, Niklaus, Kol, Rebekah, and Henrik. Ayana was told by the spirits of nature that there was a land with people that had been blessed with speed and strength, so they embarked there to start their family. During this time the Mikaelson family made peace with it's neighbors and they all lived together happily. The native people in this new country were werewolves.
During a full moon, Niklaus and Henrik, who wanted to see the men turn into wolves, decided to go out at night to watch them transform, which was forbidden. One of the werewolves ultimately attacked and killed Henrik. Niklaus brought Henrik's body back to his mother, hoping she could use her magic to help heal him, but she was unable to do so. After losing Henrik, Esther and Mikael spoke with Ayana about a possible way of protecting their children from the werewolves. They wanted to protect what family they had left, but Ayana was not willing to perform the spell, as she believed it was a crime against nature. This left Esther to do the spell by herself, at her husband's urgings, not knowing she was creating what would become deadly bloodthirsty creatures, abominations of nature.
1,000 years after Esther used the immortality spell to turn her family into vampires, she repeated the spell and performed it on Alaric. Esther again changed the spell so Alaric could kill her children:
- Alaric was immune to the white oak stake unlike the original vampires.
- Alaric being faster, stronger, and now resurrected in the season five finale, Home, this makes him, along with Klaus, one of the most powerful beings in the TVD universe with less weaknesses than other Originals. Yet, it is unknown if Elena's life force is still tied to him as she is a vampire, meaning it is uncertain that if she were to die as a vampire, then Alaric could die as well.
- After his resurrection, Alaric's immortality is either bound to the White Oak Stake, because with no life force binding spell would make Alaric a true Original by drawing his immortality from the White Oak Tree, or as Elena is a vampire now his life is bound to Elena's vampire self, or he could be truly Immortal upon resurrection as the spell Esther used to bind his life force to Elena's was broken upon their deaths.
- The different versions of the Immortality Spell was administered differently to its subjects.
- Qetsiyah created an elixir that granted immortality while Esther created a ritualistic spell that drew on objects found in nature with stages such as dying to awaken in transition, making the person undead and unable to physically age, and more blood to complete and get all the superhuman abilities that not even Silas has.
- Esther is the only one that has been seen performing this spell so far.
- While Qetsiyah's spell granted a person unconditional immortality, Esther's spell only granted conditional immortality. Contrary to Amara and Silas, the Original vampires were immune to most weapons but not all.
- According to Bonnie, Qetsiyah's version of the spell made Silas truly immortal without any weaknesses, other than the cure.
- It has been implied that the reason Qetsiyah was able to grant immortality with little to no weaknesses was mainly because the Spirits did not exist during her lifetime to create consequences for her spell. However, since the Spirits did exist during Esther's lifetime, the Spirits created side effects so that her children could not achieve true immortality, as the magic Esther drew from Nature was controlled by the Spirits. It's been theorized that Qetsiyah used Expression to create the immortality elixir.
- The Kindred were placed in the Dowager Fauline Cottage for dabbling in Immotality spells and necromancy. Meaning Esther hasn't been the only witch trying to do a version of the spell created by Silas and Qetsiyah.
- Esther's sister Dahlia performed a similar spell that would place her niece Freya and herself into a magical slumber for 100 years, then wake up to live 1 year before the cycle repeats. The spell protects from all manner of harm, granting indestructability similar to the Originals. This spell acts like an immortality spell; however, a witch retains their power, with their magic growing during each slumber.
- Dahlia's spell was used to allow her and her niece Freya, a source of her power, to keep their access to magic while being indestructible at the cost of sleeping for 100 years after being awake for one year. This prevented them from becoming immortals without access to magic such as Originals Vampires and true Immortals.
- The Cure: The cure was the only known loophole to the spell, created by Qetsiyah herself, it was the only thing able to cure the immortal.
- White Oak Stake: As Esther bound the spell to the white oak tree for immortality, it was the only thing capable of killing the Originals, once and for all.
- White Oak Ash Daggers: Forged by witches, the silver daggers were able to neutralize an Original until the dagger was removed. A gold dagger was made by Kol and Davina to work on Klaus from a silver dagger. It was the only dagger capable of neutralizing the Original Hybrid until it was destroyed by Dahlia.