The Vault - Fallout Wiki

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The Vault - Fallout Wiki
The Vault - Fallout Wiki
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Weston Lesko
Weston Lesko.jpg
Biography and appearance
RaceHuman, Caucasian
LocationMarigold Station
Dialogue FileWeston Lesko's dialogue
Nectar Collecting for Fun and Profit
SPECIALStrength: 3
Perception: 6
Endurance: 3
Charisma: 4
Intelligence: 8
Agility: 6
Luck: 5
Derived StatsHit Points: 45
Tag SkillsExplosives: 50
Medicine: 54
Science: 54
Base ID000307c8Ref ID000393eb
ActorMike Rosson

My experiments are of a complex nature and would take a scientist to explain... oh wait! I'm a scientist! How marvelous!

Dr. Weston Lesko is a scientist living in Grayditch in Fallout 3.


Lesko is responsible for creating the fire ants that carried off or killed almost everyone in Grayditch. He was experimenting on giant ants, trying to return them to their normal size through genetic manipulation when he accidentally created the fire ants using the local F.E.V., Batch 11-111 which he found somewhere around the Capital Wasteland[1]. Despite the death and destruction his experiments caused, Lesko has remained indifferent to the lives lost, stating, "At the cost of a few, generations shall be saved".[2]

[3] [4] [5]

Daily schedule

  • Until the quest Those! is completed, Lesko can be found deep underground in the Marigold Station. He will usually be in his laboratory outside the hatchery, or he might flee a short distance into the hatchery itself.
  • Lesko will not return to his shack until Those! is fully completed. This means the Lone Wanderer must also find a home for Bryan (or refuse to do so) and receive the experience points for this quest before Lesko will return to his shack.

Interactions with the player character

Interactions overview

Icon severed ear.png
This character drops an ear when killed (Contract Killer).
This character starts quests.
Perk empathy synthesizer.png
This character is involved in quests.


  • Those!: Doctor Lesko requires the Lone Wanderer's help to regain control of his experiment. If the Lone Wanderer has a high enough Science skill and Intelligence, an additional dialogue option appears when asking Lesko about his experiments. When chosen, Lesko reveals that he has been using F.E.V. in his experiments. An additional dialogue option will also appear if the Lone Wanderer has chosen the Entomologist perk, which upsets the doctor slightly.
  • Nectar Collecting for Fun and Profit: After completion of "Those!", Lesko will pay for samples of fire ant nectar. Be aware that entering Doctor Lesko's shack will be considered trespassing, even though the Lone Wanderer might have to enter it to give him some nectar. Stay there for too long, and both the protectron and Doctor Lesko will open fire on the Lone Wanderer.


Icon armored vault suit.png
Lesko's lab coat
Reading glasses
Assault carbine icon.png
10mm pistol
Icon briefcase.png
Carried items
Icon male severed head.png
Drops on death


  • It is evident that Lesko feels little to no remorse about the lives his experiments have cost, stating only that with a few losses, generations will be saved in the end. He supports the Lone Wanderer's decision to find Bryan Wilks a new home, but only because he will no longer be pestered by Bryan's questions.
  • Lesko can sometimes be killed by fire ants if the Lone Wanderer leaves both doors to his office open. Close them after speaking to him to ensure he is not killed before the Lone Wanderer has completed his quest.
  • If the Lone Wanderer doesn't select the extra payment option during the quest, they cannot obtain Lesko's lab coat. Killing him after completing the quest will net just a loss of Karma. The clothing he has on him is just a normal lab technician outfit.
  • Be warned if the Lone Wanderer decides to wait and get the perk later, for example, to use the bonus to Perception or Strength to get 10 in all attributes, if the Lone Wanderer completes 'Those' when the Doctor has returned to his shack, the Lone Wanderer is no longer able to get the perk as the speech option is now gone.
  • Lesko has found another source of F.E.V., which he has used to speed up the mutations of the ant colony. This can be discovered by questioning his methods and passing a speech check.

Notable quotes

  • "What a distressing development!!"
  • "I will blind you with science!" (when hostile via Mesmetron)
  • "Science always triumphs!" (when hostile)
  • "You've manifested yourself!" (when hostile)
  • "Your arrival was most unexpected, but not entirely unwelcome"

Behind the scenes

  • Lesko is named after James R. Lesko, a character from the film Phase IV, who is also a scientist who has to deal with "ant problems."
  • If Lesko turns hostile, he may shout, "I will blind you with science!" - a possible reference to the Thomas Dolby song, She Blinded Me With Science.


Weston Lesko appears only in Fallout 3.


  1. The Lone Wanderer: "Something isn't right. You shouldn't have gotten results like these so quickly."
    Weston Lesko: "Well... ummm, I may have used a few... ahem, shortcuts. Yes. I was told that the FEV works wonders when used under controlled circumstances! Apparently I was wrong, but I know my mistake. I'm certain I can get it to work!"
    (Weston Lesko dialogue) Note: EXPLANATION HERE
  2. Fallout 3 Official Game Guide Gama of the Year Edition p.69: "Doctor Lesko
    Lesko is a somewhat befuddled and misguided scientist whose experiments on ants have proven disastrous for Grayditch. Deep inside Marigold Metro Station, he carries out his research, completely oblivious to the destruction that his Fire Ants have caused. He has little patience for anything beyond his scientific acumen and dismisses his failures as only temporary obstacles on the road to success. While his motivation is to save the Wasteland, his methods are in fact destroying it."
    (Fallout 3 Official Game Guide Game of the Year Edition Wasteland Census)
  3. Doctor Lesko's notes
  4. Grayditch terminals
  5. Marigold station terminals