What is Cold Harbor in Severance season 2? All the theories

Episode 5 saw Helly (Britt Lower) grappling with being back on the Severed floor and with the idea that her Outie, Helena, had impersonating her all this time - and Mark (Adam Scott) hadn't even noticed.

MDR has also been grappling with the loss of Irving (John Turturro) with the help of Ms Huang (Sarah Bock) and her theremin after he exposed Helena's secret at the ORTBO - and almost drowned her.

Meanwhile, Mark's reintegration with Reghabi (Karen Aldridge) appears to be working, as he starts to remember snippets from his life inside Lumon - including his wife Gemma/Ms Casey (Dichen Lachman).

But the higher-ups at Lumon seem very concerned with Cold Habor and with Mark finishing the project.

But what is it and could it be the key to why Lumon was created? And what does it have to do with Gemma/Ms Casey? Here's everything we know so far.

What is Cold Harbor in Severance season 2? All the theories

Cold Harbor is a project that Mark S is working on at Lumon Industries, which appears to have something to do with his wife Gemma (AKA Ms Casey).

In episode 5, Mr Drummond claims that when Cold Harbor is finished, it will be "one of the greatest moments in the history of this planet," indicating that the project is likely some kind of pioneering experiment.

In episode 2, it's made clear that this project is of vital importance, with the Lumon board giving Mark S what he wants (to be reunited with his MDR colleagues, including Britt Lower's Helly R), so as they can guarantee that he'll finish the project.

It's also made clear that it's a project that only Mark can complete – fuelling theories that it's got something to do with his wife Gemma/Ms Casey. At the end of season 1, Mark's Innie discovered that Gemma and Ms Casey are the same person and that she's actually alive – despite his Outie believing she's dead.

Suddenly, the face of Mark's wife appears on-screen alongside all the information (various different numbers) about Cold Harbor, suggesting that she's got something to do with it.

In episode 5, Cold Harbor is referenced even more explicitly, with Helena being told that Helly must go back to the Severed floor otherwise Mark won't finish the project.

With Drummond saying that Cold Harbor will result in "one of the greatest moments in the history of this planet", clearly the project has huge worldwide implications.

Even the employees at Lumon don't know what they're working on, only being told that they must sort numbers that evoke an emotional reaction into folders. They're given quotas and have to finish number files before they expire.

Interestingly enough, Cold Harbor was previously used as a code name for Severance during filming and casting calls.

The tempers

One previous popular theory is that the numbers represent the "tempers", which are part of a philosophy put forward by Lumon founder Kier Eagan (Mark discovers this when he visits the Perpetuity Wing in season 1 episode 3 and has it explained by a wax figurine of Eagan, which is referenced again in season 2 episode 1).

According to Eagan, the ratio of the four different tempers, Woe, Frolic, Dread, Malice make up a person's character.

If you look closely at the bottom of Mark's screen during the end of season 2 episode 1, there are four different progress bars, with the initials WO, DR, FC, and MA.

The initials on the progress bars line up so well with the tempers that it surely can't be a coincidence. But that still doesn't answer what exactly the work is.

Gemma/Ms Casey's face appearing is potentially our biggest clue to date. Are Lumon employees like her being tested on? Are the MDR team somehow able to control a person's tempers by through the number sorting?

Resurrecting Kier Eagan

One other big theory is that all of this is leading to the resurrection of the Lumon founder Kier Eagan.

Throughout season 1, Kier is portrayed as a god-like figure and Lumon as somewhat of a cult, so it wouldn't be outside of the realms of possibility.

Another part of the show that we don't have answers for just yet is the goats. What are they for?! One theory is that the goats are being experimented on to find new ways of potentially resurrecting Kier.

Maybe the answer to resurrecting Kier lies in the numbers being refined at MDR, with his DNA being encoded.

Why does Ms Casey appear on the Cold Harbor file?

At the end of season 2 episode 1, Ms Casey/Gemma's face appears on the Cold Harbor file. The reasons for this have not been confirmed yet but, again, there are some theories.

Could Ms Casey be spying on Mark somehow through his computer? Ms Casey seems to have a completely different personality to Mark's wife Gemma, so perhaps her Innie persona could have been completely indoctrinated by Lumon, turning her against him.

Or maybe Mark is experimenting on Ms Casey somehow in his work, without being aware.

As mentioned above, perhaps the numbers do correlate to the tempers and Mark is somehow playing with these, impacting Ms Casey's personality and temperament.

To make matters more confusing, Mark's Outie confirms in episode 2 that he identified Gemma's body when she died. How could this be possible? Have Lumon cloned Gemma? Have they resurrected her?

Perhaps there's something else interesting about Ms Casey to Lumon that's yet to be revealed – but it definitely seems like there's more to her story.

What the creators have said

Creators Ben Stiller and Dan Erickson have previously been asked about what the work is at Lumon.

Erickson told Moviemaker.com: "We do have an answer in mind for it.

"It’s something that we sort of tried to weave into what’s already there in the show… the themes and stuff that are being explored from the very first episode. How do you take that and expand it to a macro level where it feels like the show is all about one thing?”

He added: "I don’t think people are going to be talking about the big twist of what the company was doing. You can make it important and resonant, but I don’t think it’s the main thing."

Severance season 2 is airing weekly on Apple TV+. Season 1 is available now.

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