999 was the conspiratorial contact of Flavia Stabo in her investigations into the mysterious deaths and the construction of Vault 79.
Background[]
999 most likely worked at the Clarksburg post office, where they programmed a deadman switch to activate automatically in the event Flavia Stabo did not make it back from her investigation of the Vault 79 site in time. They also had a side business that had some major issues, causing them to have to leave town.[1][2][3]
Appearances[]
999 is mentioned only in Fallout 76, introduced in the Wastelanders update.