Moira Brown

 is the eccentric inhabitant and owner of the Craterside Supply store in Megaton. She tasks the Lone Wanderer with helping write The Wasteland Survival Guide, doing tasks such as scouting a nearby Super Duper Mart for food and medicine, or contracting radiation poisoning to study ways to treat it efficiently.

Moira was born in 2253 in the trading community of Canterbury Commons, but ended up settling down in Megaton.

Personality
Moira's personality is extremely cheerful at all times, often excessively so. She takes as much delight in talking about what she's doing as possible. She remains inappropriately cheerful in even the most serious of circumstances. She is also extremely gullible. Almost every time after completing a mission for her you have the option to make her believe something completely ridiculous. An example is after finishing the mission from the third chapter of the book in which you must retrieve archives from a library filled with Brotherhood of Steel Paladins and Raiders. After returning with the archives, she asks you about the library's condition. A dialogue option will then appear that tells her the librarian is on duty and that you would have brought her a gift, but you forgot your library card. She'll then believe that the library was untouched by the war and is still up and running. This can be particularly amusing because the player has the option of saying just about anything nasty to Moira and she will not be offended. She is one of the only characters to do this with other than Beatrice. she takes great delight in her research, which, aside from that of the wasteland survival guide, includes domesticating mole rats, super mutant diet, and whether or not brahmin heads learn independently. Although she may not realize the full extent of her research, it would likely be a pivotal point in the revival of modern life and science

Related quest: The Wasteland Survival Guide
Moira wants you to do some dangerous research for a book she is writing entitled The Wasteland Survival Guide.

At multiple points of this quest line you can attempt to convince Moira that writing the guide is pointless and that she should center on more important things. If you do convince her to stop writing though, you will gain negative karma, and the Dream Crusher perk which causes anyone attacking you to have 50% less chance of scoring a critical hit. It also causes Moira's mood to mellow out and focus on her store, thus giving the player a discount on all items she sells (however this discount is negated if you enter the buy/sell screen through the house upgrade speech option). Her repair skill increases from 52% to 72% as well.

Blowing up Megaton
If the player character helps Mr. Burke detonate Megaton's nuclear bomb in The Power of the Atom quest, Moira survives the blast as she was outside of town researching for her guide at the time. She even remarks on how an experiment of hers, a Nuka-Psycho hybrid substance, might be responsible for the explosion. However, the massive exposure to radiation transforms her into a ghoul. She will then relocate to Underworld. She does not appear to know she's a ghoul at first, but even if the Lone Wanderer points it out, her sorrow is extremely short-lived. Typical for her personality, she optimistically realizes that she's always wanted to run some experiments on ghouls and can now use herself as a subject. Moira will still offer the quest The Wasteland Survival Guide after she becomes a ghoul. Curiously enough, if she becomes a ghoul her voice will not have the raspy trademark of a typical Wasteland ghoul (this is likely due to the additional work that would have been involved in re-recording all of Moira's script). If Megaton is destroyed after you've either completed The Wasteland Survival Guide or convinced her to abandon it, she continues to behave as if she is still running her store. You will not be able to tell her she's a ghoul, and the only dialogue option available (besides the The Replicated Man) is to repair your equipment. If this happens, she appears to remain at the Megaton Ruins permanently.

Appearances
appears in Fallout 3

Bugs

 * Occasionally, Moira will not move from the Megaton ruins after the town has been destroyed if you have completed the quest The Wasteland Survival Guide. She will stand in front of Megaton and can only repair.
 * Sometimes she will get stuck in the DC river on her way to Underworld, when talking to her in the river. Occasionally her head will spin 360 degrees, mostly when handing you items.
 * On one particular occasion, killing Moira after destroying Megaton with the atom bomb, will still for some odd reason cause her to show up in the Underworld (PS3).
 * Sometimes, if you kill Moira before blowing up Megaton, you can find her ghoulified body in front of the entrance to Underworld.
 * Strangely, her voice doesn't change after being ghoulified. As all other ghouls sound like an elderly sick person.
 * Sometimes, when Moira is killed and you loot her supplies, She will still say, "Hey, that's valuable junk!" even after she is dead.