A Meeting of the Minds A Meeting of the Minds is a " Fallout 3 " main quest and achievement that is added to the game with the " Point Lookout " add - on . Detailed walkthrough . After watching the Calvert Mansion explode , you can enter the Panic Room through a hatch in the ruins . There is some minor loot including ammunition and food , such as a Nuka - Cola Quantum and two very rare gum drops . This mission begins slightly differently depending on who you sided with in Thought Control , either Desmond Lockheart or Professor Calvert . In either case , make your way to the Point Lookout Lighthouse where a section of the floor slides away . The final showdown takes place in St . Aubin medical facility , a secret underground lab . Sided with Desmond . You installed the cogwave jammer and sided with Desmond . ' Note : This route makes Desmond essential until the final choice . Sided with Calvert . You destroyed the cogwave jammer and sided with Calvert . Making Your Way to the Brain . Once inside the lab , begin making your way down with Desmond , fighting turrets and several robobrains along the way . You can let Desmond run ahead and engage first ; if hit enough he will become unconscious but will not die . If you have the Robotics Expert perk , then you may be able to deactivate the robobrains while they are distracted by Desmond . Take your time to loot each area because Desmond will usually not run ahead . The first room on the left from when you enter the lab includes three first aid boxes and a Gatling laser . In the next room directly downstairs , use the terminal to deactivate the turrets and pick up a Mesmetron power cell and microfusion cells . If you delay long enough , Desmond will start to dance impatiently in front of the door . In the next section , the first room on the left includes several types of energy weapon cells . The first room on the right is Dr . Stewart ' s office and includes an average safe with a Stealth Boy and other random loot , an ammo box with microfusion cells , and three pre - War books . The terminals in this room and those thereafter contain background notes on the lab . The last room before the stairs includes several more energy weapon and Mesmetron cells . The stairs lead to a round room ( also with Mesmetron cells ) with two doors , one open . In the room on the right lies a Level Beta security badge for access to the next area . A robobrain sentry is stationed behind a locked door in this room that has the same badge . The next level down has operating rooms ; the second room on the right houses a bunch of chems and another robobrain . It has the Level Beta security badge ; a copy of it lies on a table in the corner . Use the terminal to unlock the door at the end of the hall . The next room has an easy safe with a Stealth Boy and a lot of caps , as well as another Gatling laser and more energy weapons / ammo . More stairs lead down to a hallway with several doors , all leading to bunks . Continue forward and you and Desmond will eventually reach Calvert ' s room , where you ' ll see the Brain himself in a massive glass tank surrounded by inactive protectrons and several fake protectron statues . Who to kill ? If you have not already killed Desmond , it is time for the final choice . You can wait for Desmond and Calvert to have a short , angry conversation , each of them claiming to have your support . ( If you wait long enough , the dialogue will begin to loop . ) Eventually you ' ll be forced to decide which of them to kill . If you speak to Calvert , he ' ll offer the greatest thing any human could ever hope for in exchange for your killing Desmond . You now have a decision to make . . . Killing Calvert . If you side with Desmond , shoot at the Brain ' s glass tank until the glass shatters or attack one of the docile protectrons . ( Desmond becomes temporarily essential until Calvert is completely dead . ) After the Brain is dead , any remaining robots will be disabled and you can talk to Desmond . He will be overjoyed to have finally won and remarks that everything that Calvert stole from him is finally all his ( although he ' s still a bit rude to you ) . Desmond gives you the exit key . After speaking to Desmond again , he will tell you that after he ' s done in the lab he will go north to confront another one of the " players " . He refers to this contest as a " microcosm of the old world " . You also have the option of killing Desmond as well , but it is not mandatory . Killing Desmond . If you side with Calvert , simply shoot at Desmond or place a grenade in his pocket . ( Calvert becomes temporarily essential until Desmond is completely dead . ) Once Desmond is dead , the Professor will reward you with the greatest thing any human could ever hope for . . . DEATH ! At least he ' ll try , at which point he ' ll send some of the previously inactive protectrons after you . You must now kill Calvert as well , because the exit is sealed until he is dead . Rewards . In the sealed room , there are 2 ammunition boxes , a safe , 2 first aid boxes , some energy weapon ammunition , some misc . items , and of course , the microwave emitter . There is also a ladder leading outside .