Season: 5-6, Episodes: 11, Faction: The Island
Jacob was the ageless protector of the Island for thousands of years. He was born on the Island and lived there, eventually in the statue of Taweret, till his brother the Man in Black convinced Ben to kill him.
Jacob spent centuries debating the nature of humanity with his brother and seeking a loophole that would let him kill him. He repeatedly left to visit potential successors whom he drew to the Island. He also served as an unseen leader by proxy for a group of Island people. After his death, Jacob reappeared as a ghost and in his youth bodily form. He finally reappeared in his adult bodily form to his last surviving candidates to pass on the position of protector.
6×01 – LA X, Part 1
A few moments after his apparent death, there appeared to be no trace of his body other than ashes. An hour after his murder, Jacob appeared to Hurley in the jungle. Although Hurley recognized Jacob from their previous encounter off the Island, he was unaware of Jacob’s identity. Jacob informed Hurley of his death, attributing it to an “old friend who had grown tired of my company.” Seeing Sayid dying nearby, Jacob told Hurley, he must be taken to the Temple if he was to be saved. Jacob further noted, the survivors would be safe there. Although Hurley did not know where the Temple was, Jacob assured him, Jin did, and told Hurley to mention the science expedition. He then reminded Hurley to bring the guitar case. Upon Jin’s arrival, Hurley could no longer see Jacob. (“LA X, Part 1”)
6×02 – LA X, Part 2
Later, Hurley informed Dogen and Lennon of Jacob’s death, who leaped into action and began fortifying and securing the Temple. Several Others were observed creating ash circles around the periphery, indicating knowledge of the Man in Black and understanding they were under threat. A signal flare was set off alerting the remaining Others at the statue of Taweret. (“LA X, Part 2”)
6×04 – The Substitute
Jacob, in the form of his younger self and with his arms and hands covered in blood, appeared before Richard and the Man in Black (in the form of Locke). Richard said he did not see the boy. Shortly afterward, the Man in Black, accompanied by Sawyer, encountered the boy again. Unlike Richard, Sawyer claimed to see the boy. The boy ran away from the two of them, and the Man in Black gave chase. He tripped, fell, and looked up at the boy, who said to him, “You know the rules. You can’t kill him.” The Man in Black became agitated, screaming “Don’t tell me what I can’t do!”
Upon the Man in Black’s return from his chasing of the boy, Sawyer asked him about the kid, to which he simply replied, “What kid?” (“The Substitute”)
Later, Ilana collected some of Jacob’s ashes upon entering the statue. (“The Substitute”)
6×05 – Lighthouse
On entering the pool room at the Temple, Hurley again encountered Jacob, who instructed him to take Jack to the lighthouse.
At the lighthouse, after Jack had destroyed the signal mirror, Jacob appeared a third time, informing Hurley he had wanted Jack brought here as there is something important on the Island that he had to do. Jacob also informed Hurley he had wanted the two of them removed from the Temple as something very bad was about to happen there. Hurley wanted to go back to warn the people at the Temple, but Jacob told him it was already too late. (“Lighthouse”)
According to Miles, up until the moment Ben had stabbed him, Jacob was hoping that he was “wrong” about Ben. (“Dr. Linus”)
6×12 – Everybody Loves Hugo
After Ilana’s death at the beach camp, Hurley searched through her belongings and found the pouch containing Jacob’s ashes and took them into his possession. (“Everybody Loves Hugo”)
Sometime later, Jacob as a boy, though with noticeably darker hair, was seen again by the Man in Black and Desmond. Desmond asked who the boy was, but the Man in Black, seemingly agitated, and this time walking away, told Desmond to ignore him. Desmond turned to look at the boy again, and the boy smiled. (“Everybody Loves Hugo”)
6×16 – What They Died For
He appeared as a boy once more to Hurley, demanding that Hurley give him the ashes. Once Hurley took them out, he snatched them and ran.
By the time Hurley caught up, Jacob appeared as an adult, next to a fire, which he had thrown his ashes in. Hurley gathered Jack, Kate and Sawyer and brought them to Jacob.
The four of them were able to see Jacob this time. He apologized to Kate, who blamed him choosing Candidates for the deaths of their friends on the submarine. Jacob told them that he made a mistake, which made the monster the way he is and explained the reason for the Candidates. Sawyer asked why he should have to suffer for Jacob’s mistake when he was doing just fine until Jacob interfered with his life. Jacob pointed out that none of them had happy lives, they were all flawed, which is why he chose them, because they were all like him, alone looking for something that they couldn’t find. Jack understood that he wanted them to kill the monster. Hurley asked, how he was going to choose, which one of them was to succeed, but Jacob left them the choice.
Jack offered to do it, so Jacob took him to a creek and told him the location of the Source, which Jack had to protect. He recited an incantation and got Jack to take a drink of water, which made Jack like him. (“What They Died For”)
6×17 – The End
When Jack made Hurley the Island protector less then a day later, Hurley worried about people being unable to leave the Island – such as Desmond. Ben told him that was how Jacob ran things and suggested there may be a better way. This led Hurley to ask Ben for help and he agreed. (“The End”)
Considering the fire eventually did go out, it is unknown what happened to Jacob’s soul after his talk with the Candidates.