Speak to Captain Curtis and then to Carrie Boyd. Do not mention to Curtis that you are investigating the break-ins, as he will try to ambush you in the tower instead of revealing his plans by reporting to the Legion.
Once you've got adequate information, visit the control tower between midnight and 1:40 a.m. If the light is already on in the tower, you can enter.
Enter and eavesdrop from the bottom of the stairs. Do not confront Curtis unless you want to kill him.
Tell James Hsu about the bomb.
Disarm the bomb with 45 Science, 35 Explosives, or the activation code, which is found on the body of Curtis the spy. The bomb is in a vent to the left side of the rear door to the forward car.
Reward: The bomb explodes when you leave the terminal building.
Reward: The bomb is defused and is no longer a threat to anyone.
Report back to Hsu.
Reward: 600 XP, 250 Caps, and NCR fame
Detailed walkthrough (NCR)
At some point, or upon asking James Hsu about problems at Camp McCarran, the Courier will be asked to speak with Captain Ronald Curtis, who is located on the ground floor of the Camp McCarran terminal building to the west of the escalators. He will then ask the player character to speak to Carrie Boyd or Contreras, although he says that Contreras is not "above" suspicion. Map markers will send the player character to Corporal Sterling, Contreras, and Boyd to ask around about suspicious activity. Contreras will refer the player character to Boyd but Sterling will provide valuable information about the spy. Speaking to Boyd will complete this part of the quest. Ask her about break-ins. She will say that there have been break-ins at the control tower every night. Ask her for an access key.
Do not inform Curtis about this lead if one wants to save the monorail. If done so, he will still go to the tower but he will not talk on the radio, and there will be no way of knowing about his plans to destroy the monorail until speaking to Hsu after confronting Curtis (or pickpocketing the codes). Being spotted by Curtis waiting outside the radio tower will also have the same effect. He will approach the player character. Subsequently, even if he is followed into the tower, he will not talk over the radio and will ambush one instead.
Go out to the control tower. The most direct route is to go out the back door between the escalators on the ground floor. Move back by one of the planes to the right (the plane closest to the wall is a good place), and wait until about 12:30 a.m.
At about 12:55 A.M., Curtis can be seen walking towards the tower. However, one can also wait until around 2:50 a.m. and enter the building, he will already be in the tower talking on the radio. If one does choose to wait outside by the planes at 12:55 A.M., the player character must remain hidden, otherwise, he will confront the player character and ask why they are there. If one ends the dialogue successfully, he will then walk back into the base and one will need to wait until the next day (unless a Speech check of 50 is passed to keep him on course after a brief return to the terminal). If Curtis starts shooting at the player character, run outside to the tarmac, then run back to the tower without firing back on him. Enter the tower and exit, Curtis will no longer be aggressive. It is possible that Curtis may not appear on the tarmac and will already be inside the tower. If the lights are on, he is already there. If he is not seen by 3 A.M., enter the tower and stay hidden as per the next instructions.
If one remains hidden from Curtis, he will walk into the tower. Follow him inside, and stay hidden at the bottom of the stairs while listening to him talking on the radio. The quest will update and tell one to disarm the bomb on the monorail. With an Explosives skill of 35 or a Science skill of 45, one can choose to go directly to the monorail, which is accessed through a door in the Northeast corner, second floor, of the main terminal building. The bomb is located inside the train car, at the air vent, next to the inside door.
Otherwise, the Activation Code will need to be pickpocketed off of Curtis for a loss of Karma. Curtis can also be confronted, in which case he will become hostile, one can kill him without loss of Karma or rep. If one kills him without confronting him, Colonel Hsu will become hostile upon reporting Curtis' death to him without giving the option for dialogue. After Curtis becomes hostile, he is fair game to kill. Then loot the Activation Code from his body. If one does not see him head into the tower, go into the tower at 2 A.M. and he should be heard in a conversation over the radio.
Once the bomb is defused, if Curtis is still alive, one may wish to return to the control tower and finish him off for the "history point" for Boone's I Forgot to Remember to Forget Companion quest. Curtis otherwise will commit suicide after being reported to Hsu. Return to Hsu, who will reward the player character with some caps and a reputation boost. Upon killing Curtis (before reporting to Hsu), the NCR guards on the tarmac may turn hostile (killing him silently should help avoid this problem), so run quickly back to the terminal. There should not be a problem collecting the reward and XP from Hsu despite the hostile guards outside.
The quest can also completed by killing Curtis in the tower before hearing the radio conversation. Upon reporting it back to Hsu, he will be surprised and state that Curtis could not be the spy as he was the leader of the investigation. After this, it will be revealed that there is a bomb on the train, the explosion of which cannot be prevented. After the train explodes, report it back to Hsu, and then the quest ends, with one gaining caps and Fame, but a lesser XP reward of 350. With the monorail destroyed, one will need a very good reputation with the NCR to complete "No, Not Much."
If your reputation with the NCR is high enough, you can get the quest from Hsu.
With a high Legion fame and an Intelligence of 8 you can tell Curtis "I know who you are, and I work for the Legion too"
Talk to Curtis, and choose the option "Hsu won't trust me enough to let me investigate". Go through the speech options until you get the quest to blow up the monorail.
Follow the map marker to the garbage can in front of the ticket counter, and take everything inside it. If you don't take everything, you won't be able to frame Davey Crenshaw.
Go to Hsu and tell him you will investigate the information leak.
Go to the monorail. If your reputation is not high enough with the NCR, you'll have to sneak by the guards. There is a changing of the guards at 9am and 6pm, making that the easiest time to sneak past. You can also disguise yourself in NCR clothing as to fool the guards.
Enter the monorail, go left, and activate a vent on the wall to plant the bomb. Note: The quest tells you to leave the monorail and watch it depart, do not leave without it blowing up as it may stop the quest from being completable.
Enter the building and go into the concourse. Go left and head to the footlocker.
After collecting all the items in the garbage can, talk to Hsu and offer to lead the investigation about the information leak. Then go to the monorail. If the player character's reputation is high enough they can just walk past the soldiers. If not, then there is a change of guards at 9 am and 6 pm, which should provide a short time to sneak to the monorail. Alternatively, the player character can put on an NCR uniform and the guards will let them pass without attacking. Now enter the monorail, turn left, and there is a vent at the end which one can activate to plant the explosive charge. The quest tells the player character to leave the monorail and watch it depart. Do not leave until it explodes, as it may stop the quest from being completed.
Back inside the building, stay on the upper level and follow the map marker to Davey Crenshaw's footlocker. Put Abraxo cleaner, conductor, fission battery, monorail sabotage plans and wonderglue into the footlocker. Head downstairs and out through the back doors. Follow the map marker to Crenshaw, who can be killed in a special way through dialogue (requires a 40 Sneak skill check.) Head back inside and speak to Colonel Hsu. The first option, telling him about the evidence, will reward 100 caps, as will the second option using speech (both are repeatable due to a bug.) The third option does not provide anything. Head back to Curtis and tell him he is in the clear for 550 XP and 150 caps.
See if you can assist Captain Curtis in his operation at Camp McCarran.
Report Colonel Hsu's refusal to Captain Curtis.
Pick up the explosives and bomb ingredients in the trash can by the ticketing counter at the Camp McCarran terminal building.
Pick up the explosives in the trash can by the ticketing counter at the Camp McCarran terminal building.
Plant an explosive charge in a vent at the back wall of the McCarran monorail car.
Get off the train and watch it depart.
Plant a fission battery, conductor, wonderglue, a box of Abraxo Cleaner, and the plans inside Private Crenshaw's footlocker.
Kill Private Crenshaw.
Report to Colonel Hsu and frame Private Crenshaw.
Return to Captain Curtis.
After completion, the evidence planted in Private Crenshaw's footlocker will always be there, including the monorail sabotage plans. There is no change in any non-player character dialogue or action when presenting the evidence.
The garbage can, with items to frame Private Crenshaw, cannot be interacted with until one is up to that point in the quest.
The player character will be killed if the monorail leaves and subsequently explodes.
If one is unable to stay hidden in order to complete the quest, there may be a Stealth Boy inside a duffle bag beside the opposite ticketing counter from the garbage can containing the explosives.
Sometimes if one has talked to the Securitrons on the Strip after the monorail blows up, they may say something like "The monorail leading from camp McCarran has been destroyed. We are working on resolving the problem."
During The Finger of Suspicion, Vulpes Inculta can trigger the quest by telling Martina that it was the Legion who sent them to protect her, then telling Vulpes that she reports to Curtis.
Behind the scenes
The following is based on non-canon behind the scenes information.
End of information based on non-canon behind the scenes information
PC Engaging in conversation with Colonel Hsu after completing the quest on behalf of the Legion results in an option to report who blew up the monorail in exchange for 100 caps. This can be repeated indefinitely.[verified]
PCPlaystation 3Xbox 360 Sometimes, after killing Curtis and obtaining the codes, the monorail will not permit entry, instead only showing 'take monorail to the strip'. [verified] To avoid this one has to speak only once at Curtis (so that the mission can continue) in order to be able to listen the conversation about him planting the bomb. If the player character tries to speak to him about this a second time, there will be a second dialogue about him saying that he will find the spy alone and once the player character goes to the tower he will attack without listening that he planted the bomb. And this will give one the only option for the monorail to be destroyed.
Playstation 3 A bug will occur on the Legion side of this quest if the player character has a high rep with the NCR if they talk to Curtis before Colonel Hsu. Curtis will talk to the player character and give them all their information, but one will not be able to get the explosives out of the trash can by the ticket desk. [verified]
Playstation 3 Sometimes, after Crenshaw has been framed, Curtis will stay in the control tower attempting to report in. Talking to him will result in his usual response when he is discovered in the tower. A possible fix for this is to sleep in an owned bed for 24 hours. Another possible fix is fast traveling to the entrance of Camp McCarran, which corrects his location. [verified]
PCPlaystation 3Xbox 360 Sometimes, as soon as the one enters the monorail area in an attempt to disarm the bomb, the Monorail will depart immediately and the bomb will detonate, even if the player character heads directly there making no stops. [verified]
Playstation 3Xbox 360 There is a bug when trying to eavesdrop on the conversation causing Victor to appear randomly standing on the steps blocking your way. No conversation is held by the NCR on the radio, thus causing the monorail to explode no matter what. [verified]
Playstation 3 After successfully entering and eavesdropping on the spy, leaving the control tower causes any followers to stop following. They will wait in front of the tower until the player character talks to them and tells them to stop following and then to follow them again. [verified]
Playstation 3 If the player character ends this quest without saving the monorail, Hsu will not grant them the reinforcements for Bitter Springs, thus making the Quest No, Not Much incompletable. However, reaching Liked status with the NCR allows Hsu to send the reinforcements before completing this Quest. [verified]
Playstation 3Xbox 360 If the player character decides to leave the tower when they are supposed to listen to the conversation and fast-travel to another location, after ~3 hours Curtis will appear and ask them what they are doing there (in another language with normal subtitles). If one ends the conversation well, he will travel back to the camp. However, one will not be able to listen to the conversation after this. [verified]
PCPlaystation 3Xbox 360 If one is on bad terms with the NCR and initiates this quest as a Caesar's Legion supporter, then get on good terms and speak to the Colonel about completing the quest for the NCR. The explosives in the trash can become non-existent and the Control Tower becomes vacant. [verified]
Playstation 3Xbox 360 Sometimes, no matter the time of day, the spy will never show up. A possible solution is to reload an earlier save. [verified]
Playstation 3Xbox 360 If Boyd got locked in the interrogation room during Silus Treatment, one will be unable to speak to her to complete this quest. One can draw her out of the interrogation room by attacking a soldier without killing them in the adjacent room. [verified]
Playstation 3 If Curtis turns hostile in the tower, 10 of Spades may suddenly appear out of nowhere. [verified]
Playstation 3 If one needs Col. James Hsu to send troops to Bitter Springs for the quest "No, Not Much", upon getting to the monorail part, get into the monorail and defuse the bomb. Then, while still in the monorail, quick travel to Fort McCarran. One should be able to go straight back to Col. James Hsu and ask him to send troops to Bitter Springs, and he will say yes. If one goes back to the monorail, it will depart and explode. This is a small workaround if one needs to get the "No, Not Much" quest completed without the monorail blowing up. [verified]
Playstation 3 After defusing the monorail bomb and reporting Curtis as the spy to Hsu, returning to the monorail results in NCR personnel becoming hostile. [verified]
PCXbox 360 There is a chance that the explosives will not be in the trash can by the ticket counter. [verified]
PCPlaystation 3 The player character may not be able to communicate with Boyd to continue the quest if they killed Silus upon first entering the interrogation room. Specifically, this happens when Silus is successfully convinced that the player character is working for Caesar through a series of Intelligence checks and then continue to attack him after Boyd asks one to leave the room while Silus is no longer aggressive. It appears Lt. Boyd is no longer able to open any dialogue with the player character after this. This can be fixed by resurrecting Silus through the Console and speaking to him again (one might need to use the Console to unlock the interrogation room door). If one's Speech is over 50 one should get a dialogue option to threaten to beat him up. If the player character chooses that option Silus will turn hostile but will not attack them; simply kill him again and leave the interrogation room. Boyd should be outside and can be talked to again. [verified]
PCPlaystation 3 One may not be able to enter the Monorail because of an invisible wall glitch before informing Hsu, to prevent this problem the player character needs to inform Hsu that they killed Curtis and then proceed to the monorail, however, there is a good chance that one will not get there in time, thus causing one to fail the quest. Alternatively, the quest can be restarted by using resetquest 000e790f in the console on PC to fix the glitch and allow one to walk onto the monorail. [verified]
PCPlaystation 3Xbox 360 If the player character helps the Legion blow up the monorail but does not have a high enough Speech or reputation level with the NCR for them to help them, they have to go back to Curtis and say "Hsu won't let me help". Curtis then tells the player character to rig the monorail to explode regardless. However, a glitch may mean that they cannot plant the bomb, making the quest impossible to complete. [verified]
PCXbox 360 If one kills Curtis and then reports to Hsu, choosing the 'You won't have to worry about Intelligence leaks' dialogue option will render the quest impossible to complete; upon defusing the monorail bomb, the monorail acts as though it detonated and can not be used to access The Strip. Upon returning to Hsu, there are no further dialogue options available. This can be fixed on PC by entering set "000e790f".breportedcurtisoutcome to 0 into the console. [verified]
Xbox 360 After starting the quest make sure to get the key to the control room from Boyd before starting the interrogation, interrogating Silus and killing him will make Boyd impossible to talk or pickpocket. Making this quest impossible as she provides the key to the control room. [verified]
Xbox 360 If the player character kills Crenshaw before the proper stage in the quest they will be sent to do so at the proper stage but will be greeted by his body, standing/floating in the spot where he died, but he will still be dead. This effectively freezes the quest and requires an earlier save in order to finish it. [verified]
Xbox 360 If one is helping the Legion, sometimes after planting the bomb on the monorail, the monorail will not leave the station, rendering the quest useless. Reloading will not help. Please see the "Fixes" section for a solution to this issue. [verified]
PCXbox 360 Upon disarming the bomb on the monorail, one will not have the dialogue option with colonel Hsu to finish the quest. [verified]
Xbox 360 While working for the Legion and going to the tram it displays: "Take Monorail to The Strip", which makes it impossible to enter the monorail. [verified]
Xbox 360 If the player character goes into McCarran around 11 pm they can see Curtis walking from his office towards the exit, the player character can then follow him outside, but as soon as they are outside they notice and tells them "I hope you catch him" or something similar and walks back into the base, however, if he is followed back in and enters a conversation, then back out again he will walk back to the doors. If one waits 10 minutes before following him out of the door he should have walked far enough for him not to detect the player character and they can safely follow him. [verified]
Xbox 360 Sometimes, when walking into the tower, the player character will not be able to eavesdrop until they have sneaked towards the top of the stairs, without him seeing them. One will then hear a voice saying, "You're too close, shamus" and immediately the [CAUTION] sign will appear and Curtis will begin looking for the player character. If one avoids his detection, he will say that he has better stuff to do anyway. However, he stays there and when spoken to will become hostile if one implies he is the spy. This means the player character finds no evidence of the bomb planted on the monorail and they will not be able to stop it going off. If the player character talks to Colonel Hsu and he tells them to disarm the bomb they may be able to disarm it but then a few seconds later the monorail still leaves and explodes, despite the quest stage having said otherwise. [verified]
Xbox 360 In some cases a bug will occur where Curtis will walk in and out of the terminal constantly, this can occur due to many other bugs and will also cause the player character to be unable to complete the quest even if the player character tells Curtis about the spy. [verified]
Playstation 3Xbox 360 Curtis may simply stand outside the control tower, never moving except to confront the player character about what they are doing. Afterward, he will remain where he is, not moving back to the terminal building. There is still a way of completing the Legion's side of the mission by injuring Curtis and having him follow the player character back to the main building. Go inside and wait for a couple of hours. (Note: one cannot wait with hostiles in the area so they must start the waiting period before Curtis enters the building.) After the waiting period, Curtis will be in the building with the player character with the dialogue to initiate the Legion side of the quest. [verified]
PCPlaystation 3Xbox 360 One may run into a glitch with Corporal Sterling after completing this quest. He will still mention noticing the light in the tower even if he is at Camp Forlorn Hope. [verified]
Xbox 360 Upon leaving the monorail after disarming the bomb it will depart and still explode.[verified]
PC Completing Silus Treatment before starting I Put a Spell on You will make Corporal Betsy not speak about suspicious activities, hence impeding the completion of the latter quest. [verified]
One possible solution to multiple issues is to use the following console commands:
set "000e790f".breportedcurtisoutcome to 0
setobjectivedisplayed 000e790f 50 1
set "000e790f".bplayertoolate to 1
Then talk to Hsu, add set "000e790f".bplayertoolate to 0
PC If one gets stuck waiting for Captain Curtis to send his radio message at the McCarran Control Tower. PC users can force the trigger on the tower up the door to be re-enabled by entering into their console set f62ab.bDoneOnce to 0. Once this console command is run the player character will have to exit the tower and re-enter it.[verified]
PC Upon collecting the explosive charge, the Courier is now committed to the Legion side of the mission and cannot use the monorail even if they fail the mission by killing Curtis. PC users can alter this by typing SetObjectiveDisplayed 000e790f 40 1 and SetObjectiveDisplayed 000e790f 70 0 in the console to switch to the NCR track.[verified]
PC If the NCR has branded the player character a terrorist for working with Caesar, Captain Curtis will attack on sight, even if one is dressed as a member of the NCR. This will render the quest impossible to complete. PC users can avoid this by opening the console, selecting Captain Curtis, and entering setav aggression 0. Captain Curtis will no longer be hostile, and all of his quest-related dialogue will be available.[verified]
PC If the player has a negative reputation with the NCR, Hsu will not begin the quest. This remains the case if the player gains a positive reputation, and so the only way to do the quest is to side with the Legion. PC players can fix this by typing set VMS08.bHsuGaveQuest to 1 in the console.[verified]