WARNING! Spoilers ahead for American Horror Stories season 2, episode 4!The disturbing ending of American Horror Stories season 2, episode 4, “Milkmaids,” is partially inspired by real history. Much like the upcoming American Horror Stories season 2, episode 5, “Bloody Mary,” episode 4’s “Milkmaids” brings to life one of Ryan Murphy’s previously proposed season themes for American Horror Story. While the disturbingly disease-ridden tale of “Milkmaids” indicates that American Horror Story will not use the popular plague theme, the spinoff’s installment certainly establishes a contemporary connection all the same.

American Horror Stories’ “Milkmaids” stars frequent American Horror Story actor Cody Fern as Thomas Browne, a Puritan New England villager in 1757. “Milkmaids” sees the smallpox disease ravage a small religious village searching for a cure, but the characters have various theories about how to slow the spread. The village’s Pastor Walter works with Thomas to test out the theory that burning the hearts of those who died from the disease can stop smallpox while eating the hearts can cure those who are already infected. Alternatively, the villager Celeste (The Politician's Julia Schlaepfer) believes the boils from her cowpox stop the cure, as all the men who drank the pus have miraculously been spared from sickness.

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Before the end of American Horror Stories’ episode, it becomes clear that the Puritans’ method for curing the disease isn’t working and that the feared milkmaids are the ones who can stop the spread. However, the religious prejudices in “Milkmaids” keep the true salvation from being revealed, with more characters ultimately dying from murder than the disease. While the disturbing nature of American Horror Stories season 2, episode 4 isn’t entirely accurate, the scientific cure for smallpox discovered in “Milkmaids” is actually based on authentic historical accounts.

What Happens In American Horror Stories' Milkmaids Ending

American Horror Stories Milkmaids Walter & Celeste

At the end of “Milkmaids,” American Horror Stories’ season 2 characters have seemingly discovered the cure for the plague. Delilah, the village milkmaid, realizes that those who have ingested the pus from cowpox boils or had cowpox themselves are spared from the sickness of smallpox. However, Pastor Walter is still intent on using his “cure from God” that involves digging up the dead, burning their hearts, and subsequently eating the organ. As Delilah tries to stop Pastor Walter and the village from digging up the dead and continuing to spread the plague, the pious man decides to go see Celeste, whose boils provide the inoculation.

Celeste kills Walter before Thomas arrives and confirms that she was the birth mother of his eldest son Edward, who has miraculously been spared from the disease. Believing that Delilah was the one who drove Celeste to “impurity” rather than himself, Thomas (AHS's Michael Langdon actor Cody Fern) tries to kill Celeste, but Delilah stands in the way and is stabbed instead. Celeste murders Thomas in return before taking the diseased cow and going to see her son Edward, who asks if she’s a milkmaid. Admitting she is a milkmaid now that she’ll be giving others the cow’s milk to cure smallpox, Edward stabs and kills Celeste. Edward then shockingly cuts out Celeste’s heart and eats it as American Horror Stories’ season 2 episode ends.

American Horror Stories Milkmaids Twist Ending Explained

Edward in American Horror Stories Milkmaids Ending

“Milkmaids” has a disturbing twist when Thomas shows his true colors as a zealot who cruelly left Celeste and took their child away due to her boils. This leads to several deaths within just a few moments, with Thomas explaining that their son Edward inherited Celeste’s wickedness. While Celeste’s reunion with Edward suggests the two will be able to leave the village and spread the cure, American Horror Stories’ episode ends with Edward killing Celeste and eating her heart. Edward decides to kill her after she admits to being a milkmaid, with the young boy repeating the pious Pastor Walter's words regarding the milkmaids being vile and untrustworthy. The American Horror Stories season 2, episode 4 twist suggests that Edward is continuing the religious extremism of the deceased pastor, which again stands in the way of the smallpox cure being revealed.

Related: American Horror Stories Season 2 Episode 2 Cast & Character Guide

Why Edward & Thomas Were Immune To The Plague

Cody Fern in AHStories Season 2

American Horror Stories season 2, episode 4, beings with the theory that eating the heart of dead bodies who were infected with smallpox can cause immunity from the disease. As such, Thomas eats the heart and tries to make Edward eat it but gives it to the cat instead. It seems that the American Horror Story spinoff's characters avoided being sick because of their exposure to the boils from Celeste’s cowpox or drinking the milk of Delilah’s infected cow. Edward being the son of Celeste, who was immune to smallpox, could have been part of why he was spared from the sickness when his sisters and step-mother all died from it. However, Thomas being immune is still curious, as he never drank the pus from the boils like the other men who survived did.

Did Puritans Actually Burn The Hearts Of The Dead To Stop Smallpox?

Seth Gabel in American Horror Stories season 2

Cody Fern’s American Horror Stories season 2 character tells Pastor Walter a story about the ritual in which burning the hearts of the dead will stop the disease. Walter then takes this idea and runs with it, getting the entire village to dig up the dead and burn or eat their hearts to cure smallpox. While cowpox does connect to how inoculation of disease was first discovered, the true history behind the American Horror Story universe's episode reveals that Puritans weren’t burning the hearts of the dead to stop smallpox.

However, there is evidence that New England Puritans used medicinal cannibalism. According to JSTOR, Puritan Edward Taylor believed in the medicinal ingestion of human flesh and blood as a substitution of the blood and body of the Sacrament. It was believed that the “mummy” flesh had been imbued with the spirit of Christ, so when it was eaten, they would be healed. In Taylor’s Dispensatory, he listed that various dead body parts could be used to help cure diseases like smallpox. This didn’t necessarily mean eating hearts like in the American Horror Story spinoff, but it no doubt inspired the American Horror Stories characters’ justification of eating the heart as the cure sent by God.

American Horror Stories True Story: Did Milkmaids Cure Smallpox?

Addison Timlin in American Horror Stories season 2

It’s been passed on through oral history that milkmaids were responsible for finding the cure to smallpox through cowpox. This is what happens in American Horror Stories, where the village milkmaid Delilah discovers that she and Celeste, who was also once a milkmaid, were never infected with smallpox because they had cowpox when younger. Delilah also realizes that Celeste’s ability to “heal” men and keep them from getting smallpox was because they were ingesting the pus from her unhealed cowpox boils. American Horror Stories’ season 2 character Delilah says they must give the villagers the cowpox-ridden milk or use the pus from Celeste’s boils for inoculation, but the pious community members resist this cure as the milkmaids practicing AHS: Coven-like witchcraft.

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According to the CDC, English doctor Edward Jenner had noticed in 1796 that milkmaids who previously had cowpox were protected from smallpox infections. The doctor theorized that exposure to cowpox could be used to avoid smallpox, so he tested this idea by taking pus from the cowpox sore of milkmaid Sarah Nelms and inoculating it in the arm of a 9-year-old boy. Jenner then exposed the boy to the virus several times, and he never developed smallpox. After testing this numerous times, Jenner inspired vaccination as a widely accepted strategy to protect against the disease.

Of course, this account has been contested much over history. According to NPR, a researcher believes the milkmaid story that inspired American Horror Stories' season 2 episode is a myth and that a doctor named John Fewster, who had been inoculating people with smallpox around 1768, was the true founder of the cowpox exposure theory. Fewster had realized that farmers and milkmaids who had cowpox were immune to smallpox and that his findings had spread to the nearby Edward Jenner, with the milkmaid story being made up to explain how Jenner discovered the usefulness of cowpox. If the researcher’s assessment of the true story is accurate, then the milkmaids like those in American Horror Stories season 2 weren’t the first people to realize that cowpox offered immunity to smallpox.

What Celeste’s Death Means For Stopping The Plague

Celeste in American Horror Stories Milkmaids

Since every character who had been told about the real prevention of smallpox was killed in American Horror Stories season 2, episode 4’s ending, the cure won’t be spread through New England quite yet. Instead, the American Horror Stories plague-themed episode's Edward Browne is apt to continue advocating for the usefulness of eating hearts and exhuming the dead as a way to stop smallpox. However, this was proven to not actually be the cure for the disease, so the villagers will continue to die despite believing that this was the prevention sent by God.

American Horror Stories’ “Milkmaids” likely ended with Celeste’s death because the real discovery of cowpox being used to prevent smallpox wouldn’t be discovered in true history until a few decades later. Had Celeste and Delilah lived and been able to spread the truth of the importance of inoculation, it would have interfered with the real-life timeline of the smallpox vaccines. As if American Horror Stories season 2 needed another creepy child in a twist ending, the plan to cure New England of smallpox in “Milkmaids” is ruined by the young homicidal Edward.