What is the Smoke Monster in Lost?

Here’s everything you need to know about his origins, his intentions and his story throughout Lost.

*Major spoilers ahead.*

How did the Man in Black become the Smoke Monster?

Claudia, the Man in Black’s mother, was shipwrecked on the island and gave birth to twins (Jacob being the Man in Black’s twin brother), with the assistance of a woman from the Island, played by Allison Janney. That woman kills their mother though, and raises them herself on the Island.

When the boys are older, the Man in Black (the Boy in Black?) discovers the other survivors of their mother’s shipwreck - known as Claudia’s People, but in reality, were part of a Roman legion - and a vision of his mother’s ghost convinces him to join with her people, against the wishes of his new foster mother.

Before he can go however, Mother shows him a cave containing a glowing light - The Heart of the Island - something that the future Smoke Monster was immediately drawn to, before Mother warned him to never enter the cave again. The boy leaves to his new people, inviting Jacob to join him, but his twin insists on staying with Mother.

Over time, Claudia’s People discover the power of the Island, and the Man in Black urges them to build a well down to the source, hoping to rediscover the light Mother showed him. His plan was to use that energy to escape the Island. Jacob told Mother of his twin’s plan though, and she incapacitated the Man in Black, filled the well and killed Claudia’s People - in which he responded by killing her in return.

Jacob would avenge Mother’s death by throwing his twin into the Heart of the Island, finally transforming him into a sentient cloud of black smoke. From there, Jacob leaves his mother and twin’s bodies in a cave, which two millennia later, Locke would find and name Adam and Eve.

How does the Smoke Monster present itself?

For so much of the show's early run, the Smoke Monster presents as exactly that, a cloud of black smoke with a mind of its own, appearing in this guise to numerous survivors in the early seasons of the show, including John Locke, who after standing his ground against the Monster, tells Michael: “I’ve looked into the eye of this Island… and what I saw was beautiful.”

He continues to appear as this Smoke Monster throughout the series, including when he kills Mr Eko in The Cost of Living, and later in season 3, he even appears to Nikki in the form of spiders. This was confirmed to be the Smoke Monster in disguise by Damon Lindelof in the Official Lost Podcast.

Outside of the Smoke Monster form, though, the other way the Man in Black presents himself is in the forms of deceased people - most notably Jack’s father, Christian, and in later seasons, John Locke.

It’s in the guise of Locke that the Man in Black sets up the endgame for his ultimate defeat, by convincing Ben Linus to kill Jacob.

What does the Smoke Monster want?

Throughout the show’s run, and for thousands of years preceding its events, the Smoke Monster/Man in Black wanted one thing: to escape the Island.

Throughout the series, this plays out in numerous ways, with the Smoke Monster attempting to manipulate figures into eliminating Jacob and his replacement candidates to be the protector of the Island - believing that in doing so, he would free himself from the Island, allowing himself to leave.

In the climax of the final season, the Monster also used Desmond Hume to, in essence, deactivate the Heart of the Island, destroying it for good and freeing himself in the process. His hubris didn’t allow him to consider that the Heart of the Island - which made him what he was - also tied him to his immortality, and with it gone, the Monster became mortal, later dying thanks to Jack and Kate.

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