Vault 81 is one of the Vaults constructed by the Vault-Tec Corporation in the Commonwealth. It is located south of Oberland Station and slightly north-west of Chestnut Hillock Reservoir. It requires either completion of Vault 81 or a high enough persuasion level to persuade security to let you in.
Although Vault 81 appears to be a control vault at first, it was originally dedicated to researching diseases and antibodies, with emphasis on potential mutations in heavy radiation. The Vault's 96 residents were isolated from the sealed scientific section of the Vault and used as guinea pigs in clinical trials of the science staff. Clinical trials were a vital part of Vault 81's mission, performed in three stages: Stage I in petri dish cultures, Stage II trials are on the colony of heterocephalus glaber specimens (mole rats), and Stage III trials on the residential population of Vault 81. The hermetically-sealed research area isolated the scientists, to reduce the chance of cross-contamination between residential and scientific staff populations. The Overseer was the only inhabitant of the residential section able to communicate with the researchers, but residents were kept in the dark otherwise.
To maintain secrecy, the Vault-Tec Operations Handbook mandated that staff members of Vault 81 participate in mandatory drills, held on-site at the discretion of the Overseer and Vault-Tec Administration. Admission drills were a requirement on all Beta Alert days, as indicated by the Vault-Tec early warning system. In the event of an actual Alpha Alert, Vault 81 residents were admitted into the Vault by Overseer's staff. All scientific staff would report to their workstations immediately, avoiding contact with general population, especially those whom they may know personally. Following the sealing of the research station, the experiment would begin. Vault 81 was not to be evacuated under any circumstances except a direct all-clear command from Vault-Tec central HQ. Research reports would be archived on the primary mainframe, with physical evidence destroyed by the Overseer and only after Stage III was completed. The residential population was considered physical evidence and would be subject to summary execution via incineration at the Overseer's discretion, unless mandated otherwise by Vault-Tec.
Of course, that was the theory. In practice, the experiment was derailed the moment Vault-Tec accepted the candidacy of Dr Olivette as Overseer. With a moral backbone and a strong sense of right and wrong, Olivette was aware that the program may include human trials and swore that should they breach ethics, he'd blow the whistle. He participated in drills just like everybody else, shocked to realize that half the science teams were medical students, cramming for finals. The pay certainly kept them happy and ensured compliance in the experiment, should it take place. But the perspective of being rich did not obscure the reality of the experiment to Olivette. When presented with the program of clinical trials as part of his Overseer briefing, he realized that he can't blow the whistle - Vault-Tec was embedded in the military-industrial complex too deep. Coupled with the good people slated for inclusion in Vault 81, he felt trapped.
Olivette did what they could to destroy the experiment: They cleared the phone list for the science staff, ensuring that none of them would be notified about future drills. When the October 23, 2077 drill began, the beta alert was soon upgraded to alpha and the Great War came. Due to the Overseer's sabotage, none of the science staff received a notification about the drill. Or not: Despite their efforts, three researchers showed up: Kenneth Collins and Jim Flint reached the Vault from the Fens with the general population, while the overachiever M. Burrow was already on site. They reported to the research area and were sealed inside. This meant that the danger to the residential population still existed.
Although there were only three of them, ensuring that the generations-long research plan would die out, they had state of the art equipment, centuries' worth of supplies, and the Contagions Vulnerability Robotic Infirmary Engineer, meaning that with even their limited manpower, they could still be a threat until they died.
To compensate for their limited manpower, Collins upgraded and modified Curie, from a customized Mr Handy, into a fully fledged lab assistant. He provided her with a custom personality, loading the databanks with every great body of work he had to make her more life-like, more... Human. And so, CVRIE became Curie. With her help, the work picked up the pace and quite soon, the Phase I trials began. When notified of it, Olivette was mortified and played for time, while maintaining an aura of camaraderie, taking care to not reveal his intentions. While the mood among the three researchers remained stable thanks to Collins and Curie, they still had access to the nozzles and could release the pathogens for a Stage III trial - or worse. When a minor mishap with the mole rat population was resolved and stage II was progressing rapidly, Olivette made the decision.
The Overseer sabotaged the delivery nozzles inside every residential quarter and room on their side of the Vault. Then, when the researchers began to notice, they disconnected the only terminal that could communicate with the science team and dumped it in the reactor chamber, near the sealed backup entrance into the science section. Sealed in the research wing, the scientists grimly continued their work, never to see the light of day again. Curie would become their inheritor, watching as they fell one-by-one. Flint was killed when a mole rat named Clyde escaped his cage. Then Collins and finally Burrow, both dying of old age. She interred them and continued the work. Finally, in 2204, Curie finally finished the broad-spectrum cure that would be capable of curing every pathogen developed and analyzed in the captive mole rats.
The Vault itself continued to operate for the next two centuries, ignorant of the dangers they narrowly avoided. The Vault, never designed for this kind of extended habitation and with the rotting, deteriorating secret partition right behind the wall, it aged badly. To compensate, the Overseer decided to unseal the Vault in 2277 and reestablish contact with the outside. Soon, trading relations established, exchanging the Vault's technology, skills, and synthesized medicine for additional food and resources to continue maintaining the Vault. Even as some dwellers continue to complain about the fact, most are well aware that without them, the Vault would collapse, if not from starvation, then quite literally.
It bought them time, but the Vault's systems continue to deteriorate and the most polite way to describe its state in 2287 is to say that it's a wreck. More importantly, the ugly secret of Vault 81 is about to rear its head - and in its most biting form... Thankfully, the reactor is still solid and continues to work - so while the Vault crumbles, everyone will be able to see at least.
The vault opens to the admission area with the security office in the north. An elevator at the end of the hall leads to the rest of the vault. The central atrium is split into the two floors: the top floor contains the depot where people can trade, the overseer's office, and a spare room (which can become the Sole Survivor's after completing Hole in the Wall); the lower floor contains the barber, cafeteria and the hallway leading down to the residential area.
Straight of the hallway is the vault classroom. The rooms lining the top and bottom of the western wing are all private residences for the vault dwellers. Directly below the classroom is the clinic, and past the classroom is the reactor room. The reactor room holds the entrance to the secret area of Vault 81, which is accessed during Hole in the Wall.
Secret Vault 81
The secret vault is a mishmash of vault architecture and cavernous dirt walls and floors, highly linear. Navigating through the busted walls of residences, leads to the small atrium which attaches to the maintenance area. The maintenance area returns to the cavernous theme, and is brimming with lab mole rats. Above the generators lies the entrance to the research, breeding, and observation area.
The observation corridor covers the depot and Overseer's office. The security gate at the end leads down further into the research wing, into the molerat breeding area. The central room has two levels, with adjoining breeding cages and laboratories. The first one on the right from the entrance contains a Master-level safe. The upper floor has a door leading further into the Vault and, on the opposite end, a small medical room with a mole rat brood mother and a steamer trunk in Vault 81 livery.
A staircase off the south side of the second floor of the cells leads upstairs to a room containing Curie as well as an elevator to get back up to the normal Vault 81.
- Syringer can be obtained from Dr. Jacob Forsythe after completing the quest Hole in the Wall.
- Taboo Tattoos: In Horatio's shop, on the table near the entrance.
- Grognak the Barbarian: Complete Short Stories.
- Medicine Bobblehead is found in the secret section Vault 81 on a table in the room containing Curie.
- Three Nuka Cherry bottles and Jangles: In a small recess near the wire fence opposite the Overseer's office observation station.
- Vault 81 Tech Password: On the table in the upper section of the molerat breeding lab, in the room next to the medical chamber.
- Stealth Boy: On the table opposite the password.
- A mini nuke
Behind the scenes
- Vault 81 was originally designated Vault 117.
Vault 81 appears only in Fallout 4.
- Survey map
- Research Comm Terminal
- Vault 81 terminals; Old Overseers Terminal, A Job's a Job?
- Vault 81 terminals; Old Overseers Terminal, Drills, Drills, Drills
- Vault 81 terminals; Old Overseers Terminal, What to do?
- Vault 81 terminals; Old Overseers Terminal, The Day
- Vault 81 terminals; Old Overseers Terminal, Science Staff
- Vault 81 terminals; Terminal, Vault 81 Mission Statement
- Vault 81 terminals; Curie's Terminal, Boot Up
- Vault 81 terminals; Curie's Terminal, Personality Profile
- Vault 81 terminals; Old Overseers Terminal, Phase I Trial
- Vault 81 terminals; Old Overseers Terminal, They Suspect
- Vault 81 terminals; Old Overseers Terminal, Forgiveness
- Vault 81 terminals; Old Overseers Terminal, Please Answer
- Vault 81 terminals; Research Comm Terminal, Please Answer
- The Sole Survivor: "These mole rats carry a disease. Do you know anything about it?"
Curie: "My poor little darlings. They were used to grow all manner of new and interesting pathogens. Then vault citizens would be exposed to these viruses in the hopes that they would develop new antibodies. But they never got a chance to execute their plan. Clyde got out of his cage. He was smarter than the others, my sweet Clyde. He let out the others and those poor scientists never stood a chance. Clyde's been dead for almost two centuries now, but his descendants have free run of the vault. I'm rambling. Where are my manners. Are you Vault-tec security?"
- Curie: "*gasp* I... I... my chest. What is happening?"
Amari: "Just breathe. It's an autonomic function. Just let your body do what it must."
Curie: "I. I feel. I feel so strange."
Amari: "Listen to me. Can you hear me? What is your name?"
Curie: "My designation is Contagions Vulnerability Robotic Infirmary Engineer. Or Curie."
The Sole Survivor: "You had me worried there."
Curie: "Do not concern yourself. I feel better now."
The Sole Survivor: "I'm not sure that's really Curie."
Curie: "Oh, but it is I. Sorry, these vocal chords are very strange."
The Sole Survivor: "Is that really you, Curie?"
Curie: "Yes. You sound so different with these ears."
Amari: "Good. Very good. Now let's test some cognitive functions. What is 1 + 2?"
Amari: "If I threw a baseball at your head, what would you do?"
Curie: "Uh. Move."
Amari: "Think of a strong memory. The first that comes to mind. Tell me about it."
Curie: "*sigh* Doctor Burrow was very old. He was the last living scientist in my section of Vault 81. He was on his bed. Very weak. He said to me, "Curie, you must..." And he died before he finished the sentence. Oh, my insides feel peculiar. What is that?"
(Amari's and Curie's dialogue) Note: This is the post-operation checkup following the quest Emergent Behavior. The three separate options for questioning Curie have been included.
- The Sole Survivor: "Yes. Yes, I am."
Curie: "Superb! I placed an emergency call so long ago. I was beginning to think something dreadful must've happened. I am pleased to report I completed my primary duties 83 years ago. Thousands of pathogens were grown in the mole rat hosts. Then a single broad spectrum cure was developed to treat them all. Very satisfying work for many decades. Now, please tell me you are authorized to release me from the lab."
- Vault 81 terminals; Overseers Terminal, The Anti-Commonwealth
- The Sole Survivor: "So there's a lot of upkeep going on right now."
Calvin Whitaker: "Hell, you can say that again. Old 81 here, she's a straight up wreck. Pretty solid for a while. Easy enough to keep up with her needs, but in the last few years or so? Damn she got feisty. Been going through tools like they were going out of style, so if you got any, I'd be more than happy to take them off your hands."
(Calvin Whitaker's dialogue)
- Fallout 4 Vault Dweller's Survival Guide Collector's Edition p.318: "[3.22] VAULT 81
Somewhere in the Commonwealth is a vault that never fulfilled its secret purpose. The people just lived normal lives for generation after generation. They are aware of the outside world but choose to remain within the safety of the vault rather than brave the dangers of the Commonwealth. They do trade with the outside world since they aren’t entirely self sufficient, so the people are used to seeing outsiders every couple of weeks or so. What secrets does Vault 81 contain?"
(Fallout 4 Vault Dweller's Survival Guide Map)
- Vault 81 terminals; Overseers Terminal, Repairs, Repairs, Repairs
- Random encounter quest RESceneJSDN077: "DN077 Vault 117 Hook- Merchant travelling to restock at Vault 117"