John Malleus

 was the chief scientist of Vault 92.

He was in charge of implementing the experiment of Vault 92 and is initially intrigued and optimistic about the results of the test. When the killings began, however, he quickly got to the bottom of the situation and discovered that Rubin had been brainwashing the musicians without controls or safety measures, turning them into violent, primal animals.

Appearances
This character is mentioned in Fallout 3 but does not actually appear in the game.