Jacob is a mysterious individual on the island. He is portrayed primarily by Mark Pellegrino and appeared in nine episodes.
Jacob is an individual who lives on the island and is the true leader of the Others, the man Benjamin Linus answers to. Little else is known about this mysterious man, other than Ben is the only person who goes to see and talk to Jacob. He harbors a distaste towards technology and Ben described him as a man you don't just go and see, but a man who summons you.
Before the Crash
Juliet Burke was recruited by the Others to help solve their pregnancy problem. She was unable to devise a solution during her stay and desired to leave the island to return home to her sister, but Ben revealed that her sister's cancer had returned. He offered to cure her sister's cancer if she stayed and continued her research, telling her Jacob said he would take care of the cancer himself. Ben would later prove to Juliet that her sister's cancer had been cured.
John Locke joined with the Others, but forced Ben to take him to see Jacob. He was brought to Jacob's cabin in the jungle, but there was no one inside and Ben held a conversation with thin air. Locke believed Ben was insane and turned to leave, but heard a voice say, "Help me." Despite Ben's prior warning of not to use any technology, Locke turned on his flashlight to confront Ben, causing the cabin to shake violently and for objects to be flung. Ben tried to stop Jacob, but was thrown back forcefully and Locke caught a glimpse of an man shrouded in shadow, sitting in the rocking chair. Fleeing the cabin, Locke was told that was Jacob. Locke still didn't believe Ben, believing it was all an act, but Ben shot Locke and demanded to know what Jacob said to him. Ben left Locke for dead upon learning the answer.
After getting lost in the jungle, Hugo "Hurley" Reyes stumbled upon Jacob's cabin. Whispering was heard in the jungle and a light began to emanate from within the cabin. Hurley looked inside through a broken window and saw Christian Shephard sitting in the rocking chair. An obscured face suddenly appeared on the other side of the window, startling Hurley who fled from the cabin. But Hurley discovered the cabin had reappeared in front of him and the cabin door opened slowly. Closing his eyes and telling himself it wasn't real, Hurley reopened them to find the cabin gone and Locke nearby.
- 5x16 - The Incident (1)
- 5x17 - The Incident (2)
- 6x01 - LA X (1)
- 6x04 - The Substitute (only as a teenager, played by Kenton Duty)
- 6x05 - Lighthouse
- 6x09 - Ab Aeterno
- 6x12 - Everybody Loves Hugo (only as a teenager, played by Kenton Duty)
- 6x15 - Across the Sea (also as a teenager, played by Kenton Duty)
- 6x16 - What They Died For (also as a teenager, played by Kenton Duty)
- 3x20 - The Man Behind the Curtain: Locke is brought to his cabin.
- 4x01 - The Beginning of the End: Hurley stumbles upon his cabin.
- Jacob: Jacob (Hebrew: "holds the heel"), also known as Israel (Hebrew: "Struggled with God"), is the third Biblical patriarch. Jacob's second wife, Rachel, died as she gave birth to Jacob's twelfth son, Benjamin. Benjamin later founded the Tribe of Benjamin, one of the twelve Hebrew tribes.