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Old World Blues
Fallout-new-vegase28099-old-world-blues (1).jpg
Quest data
LocationForbidden Zone
Given ByDr. Klein
RewardBig Mountain Transportalponder!
Make up Your Mind (optional)
Xbox Live gamerscoreIcon gamerscore.png35PlayStation 3 trophyIcon ps3trophy.pngGold
Editor ID?
Base IDxx002fcc
Related quests
X-2: Strange Transmissions!
X-8: High School Horror!
X-13: Attack of the Infiltrator!
leads to:
Gametitle-FNV OWB.png
Gametitle-FNV OWB.png

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


With all the technologies retrieved, it is time to confront Mobius at the Forbidden Zone... or is it time to confront the Think Tank?


  1. Talk to Dr. Klein after retrieving all of the technologies required.
  2. Enter the Forbidden Zone Dome entrance.
  3. Defeat or disable the X-42 giant robo-scorpion.
    1. The room farthest to the right with stair leads to a terminal that activates X-42 backup generator, which overloads and damages the X-42 giant robo-scorpion.
    2. The room on the left has a terminal that requires a Science of 50 to hack and allows turrets to turn on the X-42 giant robo-scorpion and deal some damage to it.
    3. To the right is a room that has a switch to activate the Protectron target drones, which will distract the robo-scoprion.
    4. The balcony room on the far left contains a terminal that requires a Science of 100 to hack; alternatively the password is on a holotape to the right of the rightmost protector bay. The terminal allows the option to permanently shut the robo-scorpion down.
  4. Enter Mobius' lair and reason with or kill him.
  5. Reclaim or reason with your brain.
  6. Reason with or defeat the Think Tank.
    1. To reason with them, a Speech check of 75 is required, followed by a Medicine of 85 or a Science of 100. Alternatively, if the Courier completed at least three of the four Think Tank quests (What's In A Name?, On The Same Wavelength, A Brain's Best Friend and Coming Out of Her Shell) Klein can be told to confer with his colleagues, who will support the Courier's view.

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.

Behind the scenes

  • If you finished three or more of the Think Tank's personal quests and ask Dr. Klein to consult his colleagues, having completed Doctor 8's quest, when it is his turn to speak, Klein will say, "Et 2, 8?" in response, referring to Gaius Julius Caesar's last words to Marcus Junius Brutus. It is also a reference to another quest in Fallout: New Vegas, Et Tumor, Brute?.


  • PCIcon pc.png PlayStation 3Icon ps3.png Xbox 360Icon xbox360.png When the brain is asked if it wants to be reunited with you, choosing the compromise option, the second choice, 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 you entered Mobius' room and pick alternate dialogue options.
  • PlayStation 3Icon ps3.png Xbox 360Icon xbox360.png Before entering the Forbidden Zone Dome, it is advisable to make a new separate save as when entering through the main entrance into the arena with the X-42 giant robo-scorpion, it is possible to load under the catwalk and become stuck there.
  • PCIcon pc.png Xbox 360Icon xbox360.png 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 when you have a hunger greater than zero, and, inherently, only in Hardcore Mode.
  • PlayStation 3Icon ps3.png 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. This is a similar situation to what may happen with Dean Domino in the Dead Money add-on.
    • 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 3Icon ps3.png When the protectrons inside the Forbidden Zone Dome are activated, a seemingly unlimited/invincible number of them may keep attacking the X-42, creating an effective distraction when attempting to destroy the X-42.
  • Even with all the holotapes located and installed, the only options available while interacting with the Sink Auto-Doc are heal yourself and respec your traits. This bug seems related only to the Spanish version of the game.
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 · Access Powers · All Fired Up! · 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 · Flogging a Dead Corpse · Friend of the Followers · Getting a Leg Up from Andy · 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 · Not Worth a Hill of Corn and Beans · Of Boomers and Education · Old School Ghoul · A Pair of Dead Desperados (I, II) · Papers, Please · Pistol Packing · Playing on the Old Joana · Poor Meat Never Makes Good Soup · Powder to the People · Power to the People · Proper Burial · Razzle Dazzle! · Reach for the Sky, Mister! · Rest and Resupply · Ringo's Caravan Rules · Rotface's Loose Lips · The Screams of Brahmin · Silus Treatment · Short-Term Treatment · Smooth-Talking Criminal · Strategic Nuclear Moose · Straus Calls · Strip Search · Saving (or Savaging) Sergeant Teddy · Stocking Up · Suits You, Sarah · A Team of Moronic Mercenaries · Team Spirit · The Thorn Mayhem · 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 (I, II, III, IV) · Wind-Brahmin Wrangler · You Gotta Break Out a Few Eggs · You Make Me Feel Like a Woman
Cut contentIcon cut.png Cut questsAuto-Inject Quest · Bright and Shiny · Chip Provenance · Debug Topics · Jailhouse Rock · Meat of Champions (quest) · TempMan · The Thorn Mayhem · Underpass Water Purifier · Viva Las Vegas! · Welcome to Fabulous New Vegas
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
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