What's behind the hatch in Lost? DHARMA Initiative explained

If you need a refresher, we’ve put together an explainer that does all the work for you, answering all the questions you might have had around the Hatch, its connection to Desmond, and its role in the jaw-dropping ending to the show.

Major spoilers ahead.

What is the Hatch itself?

Discovered by Locke and Boone in the season 1 episode, All the Best Cowboys Have Daddy Issues, the Hatch obviously has a longer history than just appearing at that point, and leads down to a greater mystery. But the Hatch itself plays a huge role in season 1 of the show, beginning with Locke and Boones excavation of the site, all in secret from the other survivors.

After Boone’s death, Locke goes back to Hatch, furiously banging on the door, demanding to know what the Island wants from him, before a light shines from within restoring Locke’s faith.

Unbeknownst to Locke at the time, this light came from Desmond.

Eventually, Jack decides they need to open the Hatch as a safe refuge from the Others. They do this with dynamite found on the shipwreck of the Black Rock, but not before Hurley tries to stop them after seeing the Numbers on the side of the Hatch.

Over the course of season 2, the survivors discover more about the Hatch and the station below - the Swan. The events of the season 2 finally see the Hatch, and the Swan, to implode in on itself due to the discharge of energy from Desmond’s triggering of the fail-safe system after the Numbers sequence can no longer be input.

What’s inside?

Down the Hatch is The Swan, an underground facility built by the DHARMA Initiative in the 1970s. The purpose of The Swan was to study the electromagnetic energy that emanated from that part of the Island - otherwise known as the Heart of the Island. After an incident in the '70s though, the DHARMA Initiative altered the remit of The Swan to ensure there would be no global catastrophe by accidentally releasing the Island’s energy.

This was done by having workers operate in shifts, entering the Numbers into the computer terminal every 108 minutes, periodically discharging the energy in safe amounts.

Aside from the Swan’s computer, the station itself had a few other areas. The pantry becomes an important part of the season 2 episode, Everybody Hates Hugo, but it’s the armoury that plays the larger role in the early seasons.

The survivors discover Ben Linus in the season 2 episode, One of Them, where he maintains the alias of Henry Gale, a man who crashed on the Island in a ballooning accident. His captivity and questioning becomes a major arc of season 2, ending with his escape and the reveal of his identity and role within the Others’ hierarchy.

Who are the DHARMA Initiative?

The DHARMA (Department of Heuristics and Research on Material Applications) Initiative was a research group established by Gerald and Karen DeGroot, backed by Danish industrialist Alvar Hanso and his foundation, the Hanso Foundation.

The stated goal of the group was to create "a large-scale communal research compound where scientists and free-thinkers from around the globe could pursue research" across various different fields, while also studying the properties of the Island for “the betterment of mankind and the advancement of world peace".

What are the other stations?

The Swan is one of six major DHARMA stations on the Island, along with three other facilities on the Island and one that sits away from the Island, underneath a church in Los Angeles.

The six main stations on the Island are The Swan, The Hydra, The Arrow, The Flame, The Pearl and The Orchid. There is also The Staff, The Looking Glass and The Tempest. Off the island, there is The Lamp Post.

Each facility performs a separate function, and is found by different survivors throughout the course of the series’ run.

The Hydra focused on zoological studies, with numerous cages above and below ground. The Others controlled the station, and it’s where they hold Jack, Kate and Sawyer captive at the start of season 3.

The Arrow was the facility devoted to intelligence gathering, and it’s where the survivors from the tail section of Oceanic Flight 815 lived until meeting up with the main survivors.

The Flame was the DHARMA Initiative communication hub, commandeered by the Others to monitor the rest of the Island and communicate with the outside world.

The Pearl was a facility created to monitor The Swan and other stations, with The Swan’s inhabitants unknowingly part of an experiment to monitor their behaviour.

The Orchid is the facility built around the frozen wheel, responsible for space-time manipulation.

The Staff is a DHARMA medical facility visited repeatedly throughout the show, beginning with Claire’s abduction by Ethan.

The Looking Glass was an underwater station connected to the Island’s mainland by a cable. The Others have control of it, until the events of season 3's Through the Looking Glass, where the station is partially flooded and Charlie drowns.

The Tempest is DHARMA’s chemical weapons facility, used by Ben and Charles Widmore to initiate the Purge - the Others’ act in wiping out the DHARMA Initiatives Island inhabitants.

The Lamp Post was the first facility built by DHARMA, with the sole purpose of determining the Island’s location and how to access it.

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