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For the pre-War company, see HalluciGen, Inc. (company).


HalluciGen, Inc. is a location in the Esplanade neighborhood of Boston, still accessible in 2287.


Before the Great War, HalluciGen, Incorporated was a biochemical manufacturer and innovator, aspiring to be the world leader in nonlethal technology for use by police and the military.[1]

Recently, a contingent of Gunners came to the facility on the contract of a classified client to secure pre-War military technology, particularly the facility's "InvisiWave" and "Irradicator" weapons, as well as access to the facility's mainframe and to download any available schematics.[2] However, when they accessed the lab, a hallucinogenic chemical was released,[3][4] causing the Gunners who came in contact with it to enter a murderous frenzy from catastrophic adrenal gland rupture.[5] Those that survived the initial wave died fleeing the location, shot in the back by their frenzied brethren.[6]


When the Sole Survivor first encounters the facility, the building is a mess of collapsed floors. The building opens to a reception area; a hallway to the east contains a collapsed floor that leads down to the basement, which contains an employee locker room. A hole in the wall leads into the building's maintenance room before returning to the ground floor via another collapsed floor. The subsequent hallway leads to a research office (which contains a weapons workbench). The hallway to the west goes past a conference room, a security room (including some Protectron pods), and into a break room with stairs leading to the second story. The first room out of these stairs is the accounting offices.

To access the third floor, the player character may need to walk into a wall painting blocking the doorway to the staircase, nudging it out of the way. Further, two inactive Protectrons may block the way into the first room on the third floor, requiring their destruction.

At some point, one can ascend into a corridor with several doors, which are opened by buttons. There are Gunners fighting behind each of them. As an alternative to direct combat, the player character can jump to the balcony with a staircase. This leads upstairs to a room, which will greet the player character with an announcement and invite them to test some "products."

Pressing the various buttons in this room will emit poisonous gases to the rooms downstairs housing the Gunners. A terminal in this room reveals that the rooms below were actually used to demonstrate the products to VIPs, after which the rooms should be "cleared of test subjects, blood, fluids."

A staircase to the south leads down to the basement, where the mainframe is kept. The player can either hack the door terminal directly or utilize the mainframe terminal in the adjacent room. Beyond the maglocked door are the laboratories. To the south is a decontamination chamber filled with deadly hallucinatory gas, which can be removed by using the nearby terminal to start the decontamination process. The chamber leads into the labs proper (otherwise blocked by an Expert-locked door), which contains three chemistry stations. A busted wall on the other side of the lab exits out to Boston.

Behind the building is an exterior room with a green Gun Shop sign, inside of which are a power armor station, a chemistry station, and a weapons workbench.

Notable loot

Ground level

  • Two Help wanted! notes – On the entrance reception desk.
  • Five drugged water cartons in the entrance room - One on the small table immediately to the right after entering the building from the main entrance, four more behind the reception desk.
  • Day Tripper - In the toilet tank after passing through locker/shower room.
  • Tesla Science Magazine – Entrance level, northeast corner of the building, after ascending via a collapsed section of roofing. This is the room with the research terminal controlling a HalluciGen Suppressor prototype device.
  • Note from Eric – On a desk beside the accounting terminal on the second level.
  • Two drugged water cartons in the testing chambers' locker room, down the hallway from the room with two Gunners locked in.


  • HalluciGen master password – Can be obtained from the mainframe access terminal, giving access to the lab access terminal, decontamination terminal, research terminal, and the CEO's terminal.
  • Nine HalluciGen gas canisters – All located in the same room as the Gunner commander. One unit is needed for the miscellaneous quest Hazardous Material given by Fred Allen in Goodneighbor, and only appears if that quest is active. This room is reachable from the interior by a terminal with an expert lock. Alternatively, the room can be accessed directly from the Commonwealth through a back door, north of the building, with a master lock, bypassing most combat and chemical exposure.
  • 14 ruptured HalluciGen gas canisters – All located in the same room as the Gunner commander.
  • Stealth Boy – In an open safe in the same room as the Gunner commander.
  • HalluciGen mission brief and Gunner's note – On the Gunner commander.
  • Nuka-Cola Quantum – In the same room as the Gunner commander.
  • HalluciGen key – In a steamer trunk near the north exit to Esplanade; another copy is on the Gunner commander.


  • A non-hostile female Gunner is in a locked room, as one makes their way through the building from the main entrance. She asks the player character to look through the window of her room, where they are able to talk to her. The chemical leak has almost driven her mad, and she tells the player character she can't remember anything. If they convince or threaten her to open the door, she will run to the entrance, screaming that she has to get out. She will then leave the building.
  • The special grenade, HalluciGen gas grenade, can only be made when a HalluciGen gas canister is in the player character's inventory, i.e. it will not appear as a crafting option if the canisters are placed in the workbench or workshop inventory. The canisters are regarded as "junk."
  • There are numerous canisters in the broken-out spaces near the basement-level exit. While crouching, the player character may jump on the control panel in front of the broken panel glass. From here, they can grab the ones out of reach.
  • A hazmat suit will protect the player character from the toxic gas in the contamination area. The player character will flinch as if taking damage while wearing it but will not lose health.
  • Power armor and/or a gas mask will not protect the player character from the toxic gas in the contamination area.
  • The Gunner commander may take and use the Stealth Boy, which can make it a harder fight.
  • Once activated, the decontamination equipment remains on indefinitely, and can be used by the player character to purge radiation.
  • This area is visited during the Vault-Tec Workshop add-on quests to obtain a chemical formula needed for the experiments. The formula is in the steamer trunk, making it easily accessible through the back door. It will not be present until the quest is active.
  • A non-hostile Gunner conscript is on the bottom floor, forward and to the left as one comes down the stairs. He appears to be injured, as he is holding his side and sitting against a wall. He also appears to be hallucinating from the chemical leak.
  • Companions will still complain about the smell even if they have a gas mask on (with the exception of robotic companions, such as Codsworth).
  • Reading a note found inside Marlborough house marks this location on the Pip-Boy map.
  • When at this location, companions make comments, which are activated at two locations - the entrance, and in the room overlooking the test subjects.
Location comments
Character Specific location Comment
Cait Entrance "*Coughing* Can't breathe... this stuff... it smells strange."
Demonstration control room "If you think I'm pushin' any of those buttons, you must be crazy."
Codsworth Entrance "Sir/Mum, my sensors indicate a high level of chemicals in the air. I wouldn't linger here."
Demonstration control room "I imagine these buttons may activate some changes within those rooms below."
Curie Entrance (as a Miss Nanny "My sensors detect a high level of an unknown agent in the atmosphere. I recommend extreme caution."
Entrance (as a synth) "*cough* What... What was that? This gas. In my throat?"
Demonstration control room "This whole facility is fascinating. I suggest we carefully and methodically push the buttons."
Danse Entrance "*Coughing* A chemical weapon's been deployed. We need to get out of here."
Demonstration control room "I'm not certain we should be playing with these controls. We don't know what they do."
Deacon Entrance "Shit. *cough* Strange gases. Never good."
Demonstration control room "Look at all those buttons. Go ahead. You know you want to..."
John Hancock Entrance "What the hell is this stuff?"
Demonstration control room "You wanna find out what all these buttons do?"
Robert MacCready Entrance "*Coughing* This can't be good. Hope this stuff isn't lethal."
Demonstration control room "You think any of these buttons gets us out of here and gives us a whole bunch of caps for our trouble? Yeah, me neither."
Nick Valentine Entrance "I wouldn't breathe any more of that than you have to."
Demonstration control room "Be my guest. Lord knows, I'm not pressing 'em."
Piper Wright Entrance "Ugh, this stuff burns my lungs."
Demonstration control room "You don't think those buttons will pump anything in here, right?"
Preston Garvey Entrance "*Coughing* Damn... some kind of gas... we've got to get out of here..."
Demonstration control room "Just because there's a button doesn't mean you have to press it."
X6-88 Entrance "Gas of some kind... *cough* Possibly dangerous... *cough*"
Demonstration control room "Were they performing some kind of research?"


HalluciGen, Inc. appears in Fallout 4 and is mentioned on Frederick Rivers' terminal in Fallout 76.

Behind the scenes

Brent Spiner, best known for the role of Data in Star Trek, has stated on Twitter that he may have voiced the HalluciGen mainframe heard in the building. However, he is not credited for the role and has not given a fully definitive answer.[7][8]


  • Icon pc.png Icon ps4.png Icon xboxone.png The non-hostile Gunner may not go to the window to speak with the player character. Saving prior to the encounter, exiting and re-entering the building may solve this.[verification overdue]
  • Icon ps4.png The fighting and gunfire between the gunners in the accounting terminal room may displace the Note from Eric, rendering it unobtainable. Reloading a save prior to entering the building may make it appear.[verification overdue]



  1. HalluciGen, Inc. terminal entries; accounting terminal
  2. HalluciGen mission brief
  3. Gunner's note
  4. Ruptured HalluciGen gas canister
  5. HalluciGen, Inc. terminal entries; research terminal, Lab Report: HalluciGen Gas
  6. Fallout 4 Vault Dweller's Survival Guide Collector's Edition p.447-449: "[10.02] HALLUCIGEN, INC.
    The exterior of the building has the bodies of Gunners scattered everywhere. They appear to have been shot while running away. . . . You can enter through the main doors, or locate the side entrance (Master) on the northern side of the structure, facing the amphitheater."
    (Fallout 4 Vault Dweller's Survival Guide Map)
  7. Brent Spiner on Twitter:
    @oxjamuk: "I appologiesIn-game spelling if someone has already asked this but did you record the voice for a computer on fallout 4 also I think yourIn-game spelling awesome as data but I know I'm not the first to say that. But thank you for keeping me addicted to startrekIn-game spelling"
    @BrentSpiner: "I think so"
  8. Brent Spiner on Twitter:
    @King_RolandDS: "Mr. Spiner, did you happen to voice the HalluciGen Mainframe in the VG #Fallout4?"
    @BrentSpiner: "It's possible."