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Here and now got its ups and downs, but... focusing on the past like it was any better? That's just Old World Blues.Blind Diode Jefferson, Old World Blues

Old World Blues is the final main quest of the Fallout: New Vegas add-on Old World Blues.

After completing this quest, the Make up Your Mind and Outsmarted achievements/trophies will be earned.

Quick walkthrough[]

Main Quest: Old World Blues 
Talk to Dr. Klein
Enter the Forbidden Zone
Defeat or disable the X-42 giant robo-scorpion
Enter Mobius' lair and reason with him. 
Enter Mobius' lair and kill him. 
Reclaim or reason with your brain. 
Reason with Dr. Klein. 
Kill all of the Think Tank doctors. 
Reward: Completing the add-on, the Big Mountain Transportalponder!, and the Make up Your Mind and Outsmarted achievements/trophies. 

Detailed walkthrough[]

The Courier can begin this quest by speaking to Dr. Klein, where the good doctor will tell them that it is time to go to the Forbidden Zone and get their brain back. He also asks the Courier to deal with Dr. Mobius. Optional Speech checks are available:

The player must begin by traveling to the Forbidden Zone. Once there, the Courier will encounter several robo-scorpions surrounding the entrance. After dealing with them and entering the zone itself, Dr. Mobius will release his most powerful creation, the X-42 giant robo-scorpion.

  • Enter the room further to the right with stairs that leads to a terminal, which gives the player the option of activating the X-42 backup generator, or overloading it and causing some damage.
  • Enter the room to the left and use the terminal to access turret controls (Average lock) to turn them upon the X-42 giant robo-scorpion. Although they will not be sufficient to destroy the X-42, they will cause a lot of damage.
  • Activating the Protectrons in the room to the right from the dome's entrance will distract the robot long enough to get to the shutdown terminal or other terminals.
  • Enter the balcony room on the far left side of the zone from the entrance, that contains a computer terminal (Very Hard lock). If hacked, it gives the option to permanently disable the X-42 giant robo-scorpion. Access to this room is via the stairs on the far left side of the room. If the Courier lacks the necessary Science skill, the password to the computer is on a holotape to the left of the leftmost Protectron bay.
  • Alternatively, if the Courier has the Robotics Expert perk, they can sneak up and disable it, but the X-42 giant robo-scorpion will restart itself after a set amount of time has passed.

After defeating it, the Courier must confront Dr. Mobius. To do so, take the stairs to the left of the entrance and enter the door on the right. There they will meet Dr. Mobius, who is not hostile.

Here there are two choices: kill or reason with him.

Option One: Reason with Dr. Mobius

If reasoning with Dr. Mobius is chosen, he will direct the Courier to their brain where they must convince it to return. Optional speech checks are available with him:

Option Two: Fight Mobius

If the Courier chooses to fight Mobius, Dr. Mobius will release five MK4B robo-scorpions. The player will need to defeat Mobius and the robo-scorpions in order to continue. 1066 XP will be awarded for defeating Mobius.

Once Dr. Mobius is dealt with, the Courier must then speak to their brain, and convince it to join them again. Having high Medicine, Speech or Science will give them a significant advantage and make the dialogue much easier. The use of the unique dialogue provided by Confirmed Bachelor/Cherchez La Femme/Black Widow will result in a somewhat humorous, if not mortified response from the brain that does not help much. Talking to the brain and convincing it to help in the final quest stage will grant the Make up Your Mind achievement/trophy. Optional speech checks:

  • Speech 75 (x2). Choosing to have the brain reinserted into the Courier's body will result in replacing the Brainless perk with the Big Brained perk, which yields +10% DT (Damage Threshold).

If Mobius is alive After acquiring the brain, the Courier needs to speak to Dr. Mobius again. He will tell them more about what the Think Tank is planning and suggests dealing with them, instead of him. The choice is up to the Courier.

If Mobius is dead Walk up to the Courier's brain and speak with it, thus re-acquiring it.

After making the choice, the Courier needs to return to the Think Tank. Then, the quest will end to a cut-scene. After that, the Courier will have their brain installed.

There the Courier has the option of using the Sink's Auto-Doc to retrieve their original heart and spine.

  • Choosing to replace their original heart results in replacing the Heartless perk with the Cardiac Arrest perk (healing chems are 50% more effective)
  • Choosing to replace their original spine results in replacing the Spineless perk with the Reinforced Spine perk (STR and DT bonuses doubled (+2))
  • If the Courier decides to leave their heart and spine, they can later be replaced at any time. At this point the Courier must choose to deal with the five members of the Think Tank, through violence or reason.

Option One: Reason with the Think Tank

For those wishing to reason, the speech checks are:

Option Two: Fight with the Think Tank

The Courier must destroy all five members of the Think Tank.

After completing the quest, and watching the ending slide show, the Courier is given the Big Mountain Transportalponder!. This will allow one to return to the Big MT via the Sink balcony at any time, or from Big MT to the Mojave Drive-in, although using it is limited to locations within the Mojave Wasteland, and cannot be used in areas such as the Strip or while in combat. Furthermore, upon completion, all active personalities in the Sink will cheer for the Courier's victory, with a particularly drawn-out and rambling congratulations from Blind Diode Jefferson.

After the slide show ends, (and the Courier convinced the brain to come back), the brain will either be located in the far left room, (where the heart and spine have been stored) or in the Courier's inventory. They will then be able to re-transplant or de-transplant their brain later at any time or leave it in the storage facility. Doing so will change brain, heart, and spine-related perks.

Quest stages[]

10 Return to the Think Tank and let Dr. Klein know you have completed your tasks.
20 Travel to the Forbidden Zone Dome.
25 Disable or destroy the X-42 giant robo-scorpion.
30 Confront Dr. Mobius at the Forbidden Zone Dome.
35 (Optional) Satisfy Dr. Mobius's curiosity about what it's like to be killed.
40 Retrieve your brain from the Forbidden Zone.
50 Confront Dr. Klein at the Think Tank and end your imprisonment at Big MT.
51 (Optional) Retrieve the Sink Auto-Doc's personality holotape from Y-17 to restore the Auto-Doc's functionality.
52 (Optional) Use the Sink Auto-Doc to retrieve your original heart.
53 (Optional) Use the Sink Auto-Doc to retrieve your original spine.
60 Kill Dr. Klein and the other members of the Think Tank.
70Quest finishedLeave the Think Tank.


  • The Courier can return to Big MT after the completion of this quest with the Big Mountain Transportalponder!
  • If the Courier decides to complete this quest through violence, and has not yet completed the Think Tank's personal quests, the quests will not be completable, but the message saying that the quest has been failed will not be received.


  • PCPC Xbox 360Xbox 360 After finishing this quest by either killing or talking to the doctors in the Think Tank, the game may crash as the player tries to leave. This bug occurs in hardcore mode when the player has a hunger greater than zero. If this is the case, turning hardcore off temporarily may allow to continue bug free to the end. [verified]
  • Xbox 360Xbox 360 When speaking with Dr. Klein at the end of the add-on, some dialogue may repeat when the other brains are trying to keep the player alive. [verified]
  • Xbox 360Xbox 360 If the Forbidden Zone is entered without first killing the robo-scorpions outside, upon exiting, all of the robo-scorpions will be gone. [verified]
  • PCPC Playstation 3Playstation 3Playstation 3 While entering the Forbidden Zone, the X-42 giant robo-scorpion may not attack unless it is approached. This will remain the case even when attacking the X-42 giant robo-scorpion. [verified]
  • PCPC Playstation 3Playstation 3Playstation 3 Xbox 360Xbox 360 When the brain is asked if it wants to be reunited with the Courier, choosing the compromise option, the second choice, "So, what, you'd rather just stay here? Never leaving that tank of... whatever that stuff is?", will result in a never-ending loop of the brain talking about the quests. This only seems to happen if the player has completed Come Fly With Me and That Lucky Old Sun. If this happens, reload the autosave where the player entered Mobius' room and pick alternate dialogue options. [verified]
    • An easy fix on the PC is to open the developer's console and enter closeallmenus. This closes out of the conversation for the player to try again.
  • PCPC Playstation 3Playstation 3Playstation 3 If certain choices are made in dialogue, it is impossible to reason with Mobius and killing him becomes the only option, even if the correct skill checks are completed. [verified]
    • A possible fix for this bug involves a repair check to fix Mobius' monitor, which can re-initiate the dialogue path needed to avoid killing Mobius.
  • Playstation 3Playstation 3Playstation 3 Xbox 360Xbox 360 When the Protectrons inside the Forbidden Zone dome are activated, a seemingly unlimited number of them may keep attacking the X-42, creating an effective distraction when attempting to destroy the X-42 giant robo-scorpion. [verified]


Main quests
Act 1Ain't That a Kick in the Head · Back in the Saddle · By a Campfire on the Trail · They Went That-a-Way · Ring-a-Ding-Ding!
Act 2Wild Card (Wild Card: Ace in the Hole, Change in Management, You and What Army?, Side Bets, Finishing Touches) · The House Always Wins (I, II, III, IV, V, VI, VII, VIII) · Render Unto Caesar · Et Tumor, Brute? · Things That Go Boom · Kings' Gambit · For the Republic, Part 2 · You'll Know It When It Happens/Arizona Killer
Act 3No Gods, No Masters · All or Nothing · Veni, Vidi, Vici · Eureka!
Side quests
New California RepublicAnywhere I Wander · Back in Your Own Backyard · Bitter Springs Infirmary Blues · Boulder City Showdown · Can You Find it in Your Heart? · Climb Ev'ry Mountain · Don't Tread on the Bear! · Emergency Radio · Eye for an Eye · Flags of Our Foul-Ups · Hard Luck Blues · I Don't Hurt Anymore · I Put a Spell on You · Keep Your Eyes on the Prize · Medical Mystery · No, Not Much · Pressing Matters · Restoring Hope · Return to Sender · That Lucky Old Sun · The White Wash · There Stands the Grass · Three-Card Bounty · We Will All Go Together · You Can Depend on Me
Caesar's LegionBeware the Wrath of Caesar! · Caesar's Favor · Caesar's Foe · Caesar's Hire · Cold, Cold Heart · I Hear You Knocking · The Finger of Suspicion · We Are Legion
The StripBeyond the Beef · Bye Bye Love · Classic Inspiration · How Little We Know · Pheeble Will · Talent Pool · The House Has Gone Bust! · The Moon Comes Over the Tower
Freeside & Outer VegasBirds of a Feather · Bleed Me Dry · Debt Collector · G.I. Blues · High Times · Someone to Watch Over Me · The Coyotes · Wang Dang Atomic Tango
BoomersAnt Misbehavin' · Sunshine Boogie · Volare! · Young Hearts
Great KhansAba Daba Honeymoon · Cry Me a River · Don't Make a Beggar of Me · Oh My Papa
Powder GangBooted · I Fought the Law · Run Goodsprings Run · Why Can't We Be Friends?
Brotherhood of SteelEyesight to the Blind · Still in the Dark · Tend to Your Business
OtherCome Fly With Me · Crazy, Crazy, Crazy · Ghost Town Gunfight · Guess Who I Saw Today · Left My Heart · My Kind of Town · The Legend of the Star and A Valuable Lesson · Unfriendly Persuasion · Wheel of Fortune
Companion questsED-E My Love · For Auld Lang Syne · Heartache by the Number · I Could Make You Care · I Forgot to Remember to Forget · Nothin' But a Hound Dog · One for My Baby
Unmarked questsA Bit of Slap and Tickle · A Final Plan for Esteban · Access Powers · All Fired Up! · An Ear to the Ground · Andy and Charlie · Arachnophobia · Arizona Scavenger · Barton the Fink · Bear Necessities · Big Winner (Atomic Wrangler, The Gomorrah, The Tops, Ultra-Luxe, Vikki & Vance) · Bounty Killer (I, II) · Brotherhood Bond (I, II) · Caching in at the Cove · Cajoling a Cudgel · Claws Mended · Claws Out · Dealing with Contreras · Defacing the Humble Stone · Democracy Inaction · Don't Poke at the Bear! · Eddie's Emissary · Exhumin' Nature · Fight Night · Flogging a Dead Corpse · Friend of the Followers · Gland for Some Home Cooking · Harder, Better, Faster, Stronger · Hat's Entertainment · Help for Halford · Hidden Valley computer virus · Highway to the Danger Zone (I, II) · Honorary Rocketeer · I Love Bananas · Iron and Stealing · Keith's Caravan Charade · Laurifer Gladiator · Lenk's Bad Debts · Lily and Leo · Long-Term Care · Malleable Mini Boomer Minds · Maud's Muggers · Meeting an Equal · Missing a Few Missiles · Most Wanted · Not Worth a Hill of Corn and Beans · Old School Ghoul · A Pair of Dead Desperados (I, II) · Papers, Please · Pistol Packing · Playing on the Old Joana · Powder to the People · Power to the People · Razzle Dazzle! · Reach for the Sky, Mister! · Rest and Resupply · Ringo's Caravan Rules · Rotface's Loose Lips · Saving (or Savaging) Sergeant Teddy · The Screams of Brahmin · Silus Treatment · Short-Term Treatment · Smooth-Talking Criminal · The Star Showdown · Strategic Nuclear Moose · Straus Calls · Strip Search · Suits You, Sarah · Tags of Our Fallen · A Team of Moronic Mercenaries · Thought for the Day · Tourist Traipse · Trudy's Radio Repair · A Trusted Aide · Useless Baubles or Fancy Trinkets? · We Must Stop Beating Like This · We Must Stop Meeting Like This · Wind-Brahmin Wrangler · You Gotta Break Out a Few Eggs · You Make Me Feel Like a Woman
Add-on quests
Dead MoneySierra Madre Grand Opening! · Find Collars (8: "Dog", 12: Christine, 14: Dean Domino) · Fires in the Sky · Strike Up the Band · Mixed Signals · Trigger the Gala Event · Put the Beast Down · Last Luxuries · Curtain Call at the Tampico · Heist of the Centuries · Big Winner, Sierra Madre · Return to the FountainCut content
Honest HeartsA Family Affair · Arrival at Zion · Bighorners of the Eastern Virgin · Chaos in Zion · Civilized Man's Burden · Crush the White Legs · Deliverer of Sorrows  · Departing Paradise · Flight from Zion · Gathering Storms · Gone Fishin' · Happy Trails Expedition · Prisoners of War · Retake the Bridge · River Monsters · Rite of Passage · Roadside Attraction · Sanctity of the Dead · The Advance Scouts  · The Treacherous Road · The Grand Staircase · Tourist Trap
Old World BluesAll My Friends Have Off Switches · A Brain's Best Friend · Coming Out of Her Shell · Field Research · He Came... And Went · Influencing People · Midnight Science Fiction Feature! · Old World Blues · On the Same Wavelength · Picking Your Brains · Project X-13 · Sonic Emitter Upgrade · Welcome to the Big Empty · What's in a Name? · When Visitors Attack! · X-2: Strange Transmissions! · X-8 Data Retrieval Test · X-8: High School Horror! · X-13: Attack of the Infiltrator!
Lonesome RoadThe Reunion · The Silo · The Job · The Launch · The Tunnelers · The Divide · The Courier · The End · The Apocalypse