- Talk to Overseer McNamara
- Deliver Fusion Cores to Overseer McNamara
- Misc: Follow Austin
- Misc: Talk to Dr. Forsythe
- Misc: Sit to donate blood
Vault 81. Attempt to use the vault door controls and you will be stopped by Officer Edwards and Overseer McNamara. To get in you can either hand them Fusion Core 3x or succeed on a hard Charisma check.
Once you gain entry, speak to the Overseer and obtain payment for the cores, thus concluding the Vault 81 side quest portion.
Austin who will offer you a tour of the Vault. He will escort you about the vault where you will meet the following people, some of which will have small tasks for you:
- Calvin will ask for scavenged tools in exchange for payment.
- Alexis Combes and Holt Combes who operate the Depot as traders.
- Horatio, who runs a barbershop and can change your appearance.
- Maria, runs the cafe and is also a trader.
- Katy, the classroom teacher. She will provide the misc. quest Short Stories which will net you a copy of Grognak the Barbarian.
- Dr. Penske at the hydroponics lab. She will ask you to taste Mutfruit. She will pay you for bringing her Fertilizer.
- Bobby DeLuca and Tina DeLuca in the reactor room. Bobby will offer caps for chems, to the displeasure of Tina.
After the tour, the vault dwellers will tell you to speak with Dr. Forsythe in their clinic. He will ask you to give some blood. Spending some time listening to everyone will shed some light on the original function of Vault 81.
Beyond the secret wall, Bobby won't follow you, so you're on your own. Explore the bedraggled facility which is a far cry from the clean environment of Vault 81. As you enter the area follow the path round and you will encounter several turrets and a Protectron. Deal with these and continue picking a path through the area. Soon enough you'll start to encounter the Molerat infestation. These Molerats look different to the ones you find on the surface as they're the results of experiments by the residents of the hidden Vault. They will swarm in numbers anywhere up to 8 at a time, but fortunately they don't have a lot of HP so they shouldn't present too much of an issue.
As you work deeper in the Vault you'll come across an observation room where you can hear the conversations happening in Vault 81 (if you have Nick with you he'll have some choice words about the surveillance). Read the terminals in the area and you'll discover that Vault-Tec built Vault 81 to be the guinea pigs for epidemiology and virus research. The doctors in the hidden vault were tasked with breeding new super viruses in Molerats and then unleashing them upon the unsuspecting residents of Vault 81. Make sure to check out every terminal in the area because the back story for this section is fascinating.
Continue forward until you reach a terminal next to a locked door. You may try an expert hack here or use a holotape found in a chamber near the terminal to unlock the door. Access the room, kill the vermin and speak with Curie. She will ask if you are from Vault-Tec, to which you should answer "yes" as her instructions are to trust Vault-Tec representatives implicity. She who will give you the Vault 81 Cure. She will not hand over the cure if she does not believe you to be genuinely from Vault-Tec. Before you leave the area, make sure to read Curie's terminal to find out more about the experiments and the scientists behind them. Don't forget to pick up the Medicine Bobblehead before you leave, too.
Curie will ask you to lead the way, so head back out of the quarantine lab and take the elevator back up to the main Vault. Head to the Doctor's office and speak to Dr. Forsythe. You'll have the choice here, you can opt to keep the cure for yourself or give the cure over, suffering a permanent -10 to your own health, but saving Austin in the process. Giving the cure will also earn you the unique weapon Syringer Rifle and your own room in Vault 81.
Once you have completed the quest, Curie becomes available as a Companion and asks to come with you. If you decline, she'll stay in Vault 81 but will always be available as a companion if she is needed.
- JudasBlitzkrieg - Vault 81 & Hole In The Wall Walkthrough