Who is Desmond in Lost and how did he get to the island?

So we’ve put together this nifty explainer, laying out Desmond’s crucial past, how he wound up on the Island, his purpose while he’s there, and how his journey ends.

Spoilers ahead.

What was Desmond doing before the Island?

We get quite a few explorations of Desmond’s past prior to shipwrecking on the Island, and all of them serve to flesh out his backstory. Originally, Desmond had a religious experience that led him to call off his wedding to his fiancee, Ruth, and joined a monastery as a novice monk (his repeated usage of the word “brother” comes from his time here). Ruth however, didn’t buy his claims of a religious experience, claiming he joined out of fear of commitment. This scalding leads to Desmond turning to drink, and being politely asked to leave the order, but as he does, he meets Penelope Widmore - a figure of importance in both his story, but also the wider story in Lost.

Desmond and Penelope fell deeply in love, but with one major stumbling block: Penelope’s father, Charles Widmore - a man who valued Desmond’s worth as less than a glass of MacCutcheon whiskey. Desmond eventually broke things off with Penelope, feeling that he wasn’t good enough for her, before joining up with the Royal Scots Regiment.

It’s here that things start getting a bit timey-wimey, covered in the iconic episode The Constantm - which sees Desmond’s consciousness bounce back and forth between 1996 and 2004. In a meeting with Daniel Faraday, Desmond explains that he is crossing time, only to be told that unless he finds a "constant" - something meaningful to him across both time periods - he will likely die. Desmond decides that Penny will be his constant.

Desmond meets with Charles Widmore to try and contact Penelope, which Charles allows, confident that his daughter will reject Desmond. Desmond meets Penelope, explaining that he won’t call here for eight years, as that’s the period of time his consciousness bounces forward to. She agrees, and Desmond returns to the Royal Scots, before being dishonourably discharged for reasons unknown, serving time in a military prison.

How did Desmond wind up on the Island?

After his release from prison, Desmond encounters a waiting Charles Widmore who attempts to bribe Desmond from ever contacting Penelope again. Desmond however, declines, and enters into the world sailing race that Widmore himself sponsors so as to prove his worth to both Charles and his daughter.

Desmond travels to America, where he encounters two future survivors of the plane crash – Libby, and more memorably, Jack. He also has an encounter with Penelope, who tells him "with enough money and determination you can find anyone".

While sailing the Pacific as part of the race, Desmond’s boat is hit by a storm – knocking him unconscious before he washed up on the shore of the Island.

What has he been doing since his arrival?

Desmond is dragged to "safety" by a man named Kelvin Inman, taking him to the Swan – what we commonly refer to as the Hatch – telling him there is a sickness on the island (in reality, it is the Man in Black infecting people), and Desmond may have been exposed. Over time, Desmond learns the Numbers sequence and the routine of pushing the button, despite the lack of answers to any of his questions about why they do this.

During his time with Kelvin, the latter would go out to "analyse the environment", never allowing Desmond to take up that particular task. Eventually, Desmond discovers Kelvin’s biohazard suit has been ripped, but he continues to go out – leading Desmond to wonder if the sickness is just a lie constructed to keep in the Swan. Desmond departs the Swan to follow Kelvin one day, discovering his partner fixing up his sailboat, seemingly plotting to depart the island and leave Desmond behind.

In a confrontation, Desmond accidentally kills Kelvin by dashing his head against a rock. Hurrying back to the Swan, Desmond found the countdown timer at zero and a system failure imminent due to not inputting the numbers in time. During his time away from the Swan however, an energy built up only to be released when he averted the system failure, which led to the crash of Oceanic Flight 815.

Desmond spends the next 40 days in isolation inputting the numbers, before eventually contemplating suicide. Before he can end his life though, he finds a letter from Penelope in his treasured Dickens’ novel, stating that she loves him and she will wait for him. He starts destroying the Swan, before hearing a banging on the Hatch above that turns out to be John Locke in a beautiful moment that rekindles the hope of both men within the story.

What is his role in the overall story?

Introduced in the Season 2 premiere, Man of Science, Man of Faith, Desmond plays a limited role in the season, leaving the Hatch in the first episode to sail off the Island, before returning in the two-part finale. It’s in the finale that Desmond uses the Swan’s fail-safe key with the computer destroyed, having realised his own role in the crash of Oceanic Flight 815. The discharge from the fail-safe leads to the implosion of the Swan, and Desmond’s consciousness being sent back to his 1996-self.

Desmond re-lives his experiences from the past, with flashes of the future coming back to him, while also seeing the numbers everywhere. Events play out slightly differently than the past though, but Desmond learns in a conversation with Ms Hawking that he can’t escape his fate, and that the universe will always "course-correct".

Drowning his sorrows, Desmond gets into an altercation in the pub before being hit by a cricket bat, transporting his consciousness back to the future, where he becomes a key figure on the island within the survivors group.

After turning the fail-safe key, Desmond also starts experiencing "flashes", visions into the future that become pivotal for the story, and the characters around him. Much of his arc from this point on in the show concerns his desire to change the future that he foresees - a nod to the characters namesake, Scottish philosopher David Hume, whose ideas were concerned with concepts surrounding free will and determinism.

How does Desmond’s story finish?

Like every other character, Desmond has a dual story in the final season of Lost, with events on the Island and events in the flash-sideways occurring simultaneously on-screen.

In the flash-sideways, Desmond is working for Charles Widmore as his right-hand man, and has everything he could want - apart from Penelope. When he eventually meets her though, after shaking hands he recovers memories of his past life, as well as the true nature of the flash-sideways. All of this leads him to ask for the flight manifest for Oceanic Flight 815 - a flight he was on in this timeline - to carry out his new plan.

In essence, he recruits all of the survivors, helping them all learn the truth of the flash-sideways and the reality of their time on the Island. Like everyone else, his story finishes with the church doors opening and being engulfed in white light as he and his fellow survivors "move on" together.

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