To start the Cappy in a Haystack mission, you’ll need to first talk to Sierra Petrovita. She’s a blonde woman wearing a green shirt who can be found in Nuka-Town. Talk to her, and she’ll ask you to get her a Nuka-Cola Quartz (or you can skip this by passing a dialogue check). These can be found in a few places across the park, but I found the most in the Safari Zone.
Once she trusts you, Sierra will tell you her plan to find the Cappys. These hidden pictures require you to wear the Cappy glasses that Sierra gives to you.
Hidden Cappy Locations
There are 10 hidden Cappys, each one with its own letter. Once you collect all 10, you can spell the secret word to access Bradberton’s office.
|What a hidden Cappy looks like without the Cappy glasses|
Nuka-Town USA Hidden Cappy Locations
|The hidden Cappy in Nuka-Town, hidden behind the restroom|
G - This hidden Cappy is on the outside wall of Nuka-Town. To find it, look for a red brick bathroom building, this Cappy will be off to the left.
Galactic Zone Hidden Cappy Locations
|The hidden Cappy by the Star Control employee's only area|
S - Next to the Employees Only gated area behind Star Control
|The hidden Cappy by the Spacewalk in the Galactic Zone|
To the left of the “Spacewalk” tunnel entrance
Dry Rock Gulch Hidden Cappy Locations
|The hidden Cappy on the back of a grave in Dry Rock Gulch|
E - On the backside of a grave in the graveyard opposite The Giddyup Kid
|The hidden Cappy on the side of the shack in Mad Mulligan's Mine|
H - Inside Mad Mulligan’s Mine, follow the path to the room with a waterfall and shack in it, on the side of the shack
Safari Zone Hidden Cappy Locations
|The hidden Cappy on the backside of the gorilla statue|
N - On the back of the gorilla statue outside the Primate House
|The hidden Cappy found in the hedge maze|
E - From the start of the hedge maze, take a right and then another right. You’ll find this Cappy along a wall in a dead end
World of Refreshments Hidden Cappy Locations
|The hidden Cappy on the side of the building in World of Refreshment|
R - On the side of a building in the Western section of the World of Refreshments ride
Kiddy Kingdom Hidden Cappy Locations
|The hidden Cappy in the tower in Kiddie Kingdom|
I - In the top room of the tall tower
|The hidden Cappy in the Fun House swirling room|
F - Behind a red door in the swirling room of the Fun House
Once you have found all 10 hidden Cappys, return to Sierra in Nuka-Town. She’ll be standing right next to Bradberton’s office, and tells you to unlock the door with the code. Unlock the door and go upstairs to the office.
The hidden button in Bradberton's office
There’s a hidden switch you can read about on Bradberton’s computer, or you can go find it. It’s located to the side of the Nuka-Cola machine by the desk.
Go down the elevator, and you end up in a vault, talking to the frozen head of John-Caleb Bradberton himself. He tells you there are treasures behind a locked door, and if you turn off the power you can get them (and also kill Bradberton, but he wants to die. You would too if you were a frozen head, alone for hundreds of years).
But wait, Sierra wants to keep Bradberton around. She offers you a fancy jumpsuit if you don’t shut off the power. If you want both the jumpsuit and all the goodies behind the locked door, side with Sierra to get the jumpsuit. Once you have it, just go shut off the power anyway to open the door. The only downside to this is Sierra will turn on you, and start shooting you.
The locked room has the Nuka Nuke Launcher, a modified Fatboy. There’s also some Nuka Nukes to shoot, the recipe for crafting more Nuka Nukes and the recipe for making Nuka-Cola itself. It should be noted that the Nuka Nuke Launcher cannot be crafted, so this is the only one you will be able to get. Use it wisely.
If you prefer a video guide, then you can check the video below from youtube user Hey Im Starlord below: