Welcome to the Big Empty

Welcome to the Big Empty is the first main quest

Detailed walkthrough
After being teleported to Big MT, the Courier will be standing on the balcony of the Sink, facing outwards towards the expanse of the Big Empty. Enter the nearest door into the Sink. Proceed to the elevators. Enter the right elevator to go to The Think Tank. Note that this is the only elevator that can be used at the moment. Due to an overwhelming feeling of pacifism, the Courier won't be able to draw a weapon in the Think Tank. This is so they will not be able to harm the doctors, which is a failsafe put in place after an attack on the Think Tank by Elijah, which led to 8|Dr. 8's voice module being damaged, and the destruction of the Big Empty's multiple train tunnels. When the Courier approaches the doctors, they will address the Courier, and the Courier will learn about Big MT, the various changes they have made to their body, and about Doctor Mobius.

After agreeing to help the doctors against Mobius, they will assign the Courier to the Sink Central Intelligence Unit.

Through various conversation options, the Courier will be able to talk the doctors into giving various items to help in the Courier's quest. The scientists give the Sonic Emitter - Revelation. With an Energy Weapons check of 50, more ammunition for it will be given. With a successful Guns check, also of 50, the scientists also give the Courier the K9000 cyberdog gun; with a Guns check of 75, more ammunition for it will be given. Other items include doctor's bags, stimpaks, bottle caps, and various skill magazines, after successful Barter checks of 25, 50, 75, and 90.

Bugs

 * Upon spawning on The Sink balcony at the beginning of the quest, the game may freeze. Restarting the system, and reloading the autosave will take the player right back to The Sink balcony. There is very strong, almost stand-still lag. Resetting the PS3 will usually fix this problem.
 * The lag does persist, but only if the player returns to or remains at the balcony. Reloading the save and/or restarting PS3 does not seem to help. There is always stand-still lag, even when trying to look around. Entering The Sink will usually fix this issue.
 * Avoiding the lag issues mentioned above all-together can be achieved by saving and reloading the game immediately prior to teleporting via the downed satellite.