Doctor Lesko

 is a scientist living in Grayditch in 2177.

Background
Lesko created 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. 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".

Lesko has a shack by the diner which requires Average Lock-picking Skill, or the key to enter. He can be found deep underground in the Marigold Station. He is involved in the quest Those! which can be obtained from him or alternately you will be approached by Bryan Wilks who will trigger this quest, Doctor Lesko's quest offers either Ant Sight or Ant Might as a reward, the player can choose between the two. Lesko can sometimes be killed by fire ants if you leave both doors to his office open, close them after speaking to him to ensure he is not killed before you have completed his quest.

Note: If you don't select the extra payment option during the quest, you 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.

Appearances
 only appears in Fallout 3.

Bugs

 * It has been reported that Lesko has been found dead by some players before you start the quest, so it is suggested that one does not wait too long to complete the "Those!" quest until the exact parameters of this bug has been discovered and hopefully repaired.
 * This bug can be fixed in the PC version by clicking Lesko's corpse in console mode and typing "resurrect".
 * You should get the Ant Might / Ant Sight perk immediately when offered by Doctor Lesko. If you delay getting it until Doctor Lesko is back in his shack, you might not get the dialogue option to get the Ant Might / Ant Sight perk. Also, adding the perks Ant Might (000C1A6B) or Ant Sight (000C1A6C) through the console, the fire resist may not be added to your character.
 * Lesko will not return to his shack until "Those!" is fully completed. This means you must also find a home for Bryan and receive the experience points for this quest before Lesko will return to his shack.

Behind the scenes

 * Lesko may be 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".