The Heart of the Island is a site on the Island containing water, a brilliant bright light, and high levels of electromagnetism. The Light, energy, and water radiate to other parts of the Island, albeit in much smaller quantities. Mother considered the site the source of life, death, and rebirth. The DHARMA Initiative thought it contained negatively charged exotic matter. Both believed in its power and believed it could if improperly handled, destroy the world.

The Heart is located just beyond the bamboo grove, and though its pockets cover the Island, only the current island protector can locate it directly.

Nature and purpose[]

Mother's perspective[]

The Heart's first known protector believed it to be a physical manifestation of "life, death, and rebirth". According to her, humans covet it because a portion of the light is inside every living thing — "but they always want more". Though people cannot take the light, their attempts to do so could "put it out". And if the light were to go out there... it goes out everywhere. Mother forbade her twin sons from entering the light, as such was said to cause a fate "worse than death". ("Across the Sea")

When the survivors, after death, were ready to "move on", a bright yellow light washed over them.

Jacob's perspective[]

Jacob described the island as a cork that held back a destructive force - "malevolence, evil, darkness". If this force could escape, said Jacob, it would spread beyond where it "belonged" with presumably dangerous consequences. ("Ab Aeterno")

The actual Heart contains a physical cork, revealing this description as no mere metaphor. When Desmond removed the cork, water stopped flowing into the pool, the bright light went out and a sinister red volcanic glow appeared in the hole, as though "the Island just lost its cooling system."[1] The Island, too, began to tremble and collapse into the sea. When Jack replaced the stone, the light was restored, the quakes subsided and water began to flow into the pool. Had Jack not plugged the cork back into place, the entire Island may have sunk, with grave global implications. ("The End")

The DHARMA Initiative's perspective[]

DHARMA scientists believed the Heart contains "negatively charged exotic matter", which manipulates space and time. ("There's No Place Like Home, Part 2") In real-world physics, this term refers to a type of undiscovered matter that is hypothesized to exist. This matter supposedly has bizarre anti-gravity properties that warp space in the opposite way that "normal" baryonic matter warps space, i.e. normal matter pulls space toward its center while exotic matter pushes space away from its center. This is not to be confused with dark matter (matter that does not interact with radiation) nor dark energy (a mysterious anti-gravity force that pervades the entire universe and is driving its current accelerating expansion). Eloise Hawking explained that beneath the Island is "a unique pocket of electromagnetic energy [that] connects to similar pockets all over the world." On one of these pockets, DHARMA built the Lamp Post to find another of these pockets - the Island, which periodically moves. ("316")

The Heart does indeed manipulate space and time. It teleported Jack and the Man in Black when they entered it. ("Across the Sea")  ("The End") The Man in Black tried to use an offshoot of the Light to escape the island, and the frozen wheel later built there transported people through space and time. ("The Shape of Things to Come") Another of the Heart's pockets also sent Desmond through time. ("Flashes Before Your Eyes")



The Man in Black is thrown into the Heart of the Island.

From the outside, the Heart appears as a glowing yellow light emanating from a tunnel. A river flows into this cave, ending in a waterfall. The light is considered "beautiful", "the warmest, brightest light you've ever felt". Inside the tunnel, at the bottom of the waterfall, lies a volcanic cave with a pool in the center, plugged by a rock that glows brightly. There are extreme levels of electromagnetism in the cave, higher than any other location on the Island. ("The End")

This electromagnetism appears at a number of other sites on the island that people can more easily access. Some of these include the Swan and the Orchid.

The Heart contains several ancient man-made water ducts around a pool constructed of cut stone. At the center of the pool, a chiselled stone cork plugs a gaping hole. The ducts carry the water from the Heart to other parts of the Island, perhaps including the Temple, explaining the healing Spring therein. ("LA X, Part 2")


The stone cork (or Great Stone, as the script called it) and the hole that it stoppered have markings on them. The clearest markings are cuneiform script, one of the earliest known forms of writing. Cuneiform was used by Akkadians and Sumerians in ancient Iraq circa 5000–1000 BC. According to Carlton Cuse, it's an "incredibly likely deduction" that people built this cork after the Man in Black entered the Heart, damming the flow of light. (Across the Sea audio commentary)

Four lines of ancient script spiral around the stone cork. The upper two lines are Egyptian hieroglyphs, while the bottom two are cuneiform script. (Lost Encyclopedia)

  • Line 1: "Embrace that which the Balance hath weighed, let a path be made for the Osiris in the Great Valley, and let the Osiris have light to guide him on his way."
  • Line 2: "He hath reconciled the Two Fighters (Horus and Set), the guardians of life."
  • Line 3: "Break the immovable yoke that we may sleep."
  • Line 4: "That silence may reign and we may sleep."



Jack and The Man in Black look down the cave into the Heart of the Island.

The early history of the heart is unknown, but the inside chamber was not made by natural processes, and the Mesopotamian cuneiform script is visible on the stone plug in the center of the pool.

About two millennia before the crash of Flight 815, Mother was the protector of the Heart. She lived on the Island with two children, Jacob and the Man in Black. Sometime, when Jacob and the Man in Black were thirteen, Mother walked them blindfolded to the cave, where she showed them the light. After Jacob's brother left him and Mother, he searched for the Heart for 30 years unsuccessfully, but eventually he discovered that the light could be accessed underground in spots where there is strong magnetic activity.

6x15 TheHeartOfTheIsland

Mother shows Jacob and the Boy in Black the Heart of the Island.

When Mother learned of this fact, she made Jacob the new protector of the Heart. After the Man in Black killed Mother, Jacob threw him into the light, and a roaring pillar of black smoke came shooting out of the cave. Jacob later found the dead body of his brother on a crop of rocks near a river, and laid the body to rest in the caves next to his mother. ("Across the Sea")

Jacob spent many centuries as the protector of the heart. During this time, the Man in Black tried to kill Jacob and leave the Island. Jacob was murdered by Ben in 2007, and the Man in Black then set out on a mission to destroy the Island and extinguish the Heart. Jacob appeared to his candidates and made Jack the new protector of the heart.

After accepting Jacob's position, Jack was told that the Heart of the Island was located past the bamboo forest where he first woke up. Jacob told Jack that though he may have been unable to find it at first, he would now be able to. Jacob claimed that it was at the center of the Island. ("What They Died For")


Desmond sees the source of the electromagnetism and the water ducts deep within the Heart of the Island.

When Jack met with the Man in Black, they joined up to have Desmond enter the Heart of the Island and put the light out. The Man in Black wanted to extinguish the light permanently to sink the Island, and Jack wanted to put it out temporarily so he could kill the Man in Black. Meanwhile, Desmond believed that putting out the light would take him to an alternate reality where Flight 815 had never crashed. The three of them entered the cave and lowered Desmond down with a rope. When he reached the bottom, Desmond found an ancient cave structure, and a brightly glowing rock acting as a cork in a pool of radiant light. As he approached the rock, he was bombarded with electromagnetism and passed out once he'd managed to remove the rock. The light began flashing brightly, and a series of hissing and crackling noises issued from the ground as Desmond pulled the stone out of the hole. The water drained out of the pool, and the water flowing from the pipes stopped. Heat, steam and a dark red light began issuing from the hole as the Island began to crumble into the ocean.


Desmond removes the cork from the Heart of the Island.

It was found that after putting the light out, the Man in Black was mortal. After he was killed, Jack returned to the Heart with Ben and Hurley. There, Jack, knowing that his task to reactivate the Light and rescue Desmond was a suicide mission, named Hurley as the Island's new protector.

Ben and Hurley lowered Jack into the cave, where he woke Desmond, tied the rope around him, and put the stone back into the hole. This caused the water to start running again and he placed his hand on a stream as he collapsed near the edge of the pool. The water that he touched reached the stone, and the light was reignited, saving the Island. ("The End")

Notable visitors[]

Picture Name First visit Last visit Reason for Visit
Mother "Across the Sea" "Across the Sea" Earliest known protector of the Heart. Brought Jacob and the Man in Black as children to the Heart in order to inform them of their condition as candidates. She later brought Jacob back, making him protector of the Island.
Jacob "Across the Sea" "Across the Sea" Was brought to the Heart by Mother as a child, where he learned he was a candidate to succeed her as protector of the Island. He later returned, and accepted the job. His successor was Jack.
Man in Black "Across the Sea" "The End" Was brought to the Heart by Mother as a child to learn of his candidacy to become its protector. After he killed Mother, Jacob knocked him out and throws him down the stream into the Heart. After a moment, the Man in Black burst forth from the Heart as the Smoke Monster. Later, Jacob found his brother's original body downstream from the Heart. The Man in Black returned in the form of Locke with Jack and Desmond with the goal of "putting out" the light and destroying the Island. He became human soon after the light went out, and was killed by Kate and Jack.
Hurley "The End" "The End" Followed Jack after refusing to leave the Island. There, he becomes its new protector, rescues Desmond, and hires Ben as his advisor.
Desmond "The End" "The End" Was brought to the Heart by Jack and the Man in Black. He entered the cave, and after putting out the light, he passed out. He was later rescued by Jack, who tied the rope around him and was carried out by Hurley and Ben.
Jack "The End" "The End" As protector of the Island, he visited the Heart with the Man in Black and Desmond to carry out his plan to kill the former. After achieving success, he returned to name Hurley as his successor as well as to reignite the light. He later died from injuries sustained from his fight with the Man in Black.
Ben "The End" "The End" Followed Jack and Hurley to the Heart after refusing to leave the Island. Comforts Hurley after Jack's death and accepts his offer to become his advisor, therefore gaining the role he always wanted from Jacob.

Unanswered questions[]

Unanswered questions
  1. Do not answer the questions here.
  2. Keep the questions open-ended and neutral: do not suggest an answer.
For fan theories about these unanswered questions, see: The Heart of the Island/Theories
  • Whose skeletons are near the Heart?
  • Who built the masonry around the Heart?
  • How did it turn the Man in Black into the smoke?