In the still-maintained Vault 112, the Lone Wanderer discovers several "Tranquility Lounger" simulation pods and enters the simulation. Inside, they find the simulated world of pre-War Tranquility Lane, a monochromatic locale based off 1950s society. Within this simulation are others in their simulation pods, now designated as Tranquility Lane's residents. They are encouraged by one of the residents to talk to a little girl named Betty who hangs out in the center with a dog named "Doc".
Speaking with "Betty", she reveals that she is really the assumed form of Stanislaus Braun. Having control over the simulation, Betty/Braun asks that the Lone Wanderer fulfill four tasks that will amuse her/him. Among these tasks are making a local boy cry, breaking up the Rockwells' marriage through assorted means, murdering Mabel Henderson in a "creative" way, and dressing up as a clown-masked killer called The Pint-Sized Slasher to terrorize and kill the residents. Should the Lone Wanderer choose to do this, Braun/Betty will congratulate them for a good show, reveal that "Doc" was really James in another form, and allow the Lone Wanderer to leave the system. However, Braun will just bring the residents back to life after the Lone Wanderer has left, just as he had countless times before to further his twisted amusement.
Alternatively, the Lone Wanderer can also go to the Abandoned House and, by entering the code via tapping a set of objects to the first few notes of Tranquility Lane's theme, uncover the "Chinese Invasion" failsafe. By initiating this failsafe, simulations of Chinese soldiers murder the residents, save Braun/Betty, Doc and the Lone Wanderer, and thus free them forever from Braun's control. Braun/Betty criticizes the Lone Wanderer for trapping him/her alone in the simulation, perhaps forever, but still permits the Lone Wanderer and James to leave as he no longer has control over either.
PersonalityBraun is very egotistical and condescending, often quick to insult the Lone Wanderer such as when he reveals that "Doc" is James. After years within the simulation, Braun started loving the control he had over the other Vault 112 dwellers as Overseer and began torturing and killing them over and over, only to revive them and wipe their memories clean before repeating the process. His sadism increased as the years went on.
Braun is also quick to anger. If the Lone Wanderer should attack his Betty form, Braun summons a lightning bolt to kill the Lone Wanderer (even if the Lone Wanderer has activated the failsafe). He also expresses his anger (with a hint of fear) if the Lone Wanderer activates the failsafe, thus condemning him to being entrapped within the Tranquility Lane simulation.