You Gotta Shoot 'Em in the Head

You Gotta Shoot 'Em in the Head is a side quest in Fallout 3. It is also an Xbox 360/PC achievement and a PlayStation 3 trophy.

Background
Allistair Tenpenny once hired five mercenaries: Mister Crowley, Tara, Dave, Dukov, and Jeff Strayer to find a rare weapon in Fort Constantine. In order to get a bigger share of the reward, Dukov trapped Mister Crowley (a ghoul) in a room with feral ghouls. Crowley, who survived despite what everyone else believed, is now a resident of Underworld. Tara died in Fort Constantine and the three remaining mercenaries escaped and completed the mission.

Starting the quest
Talk to Mister Crowley in the Ninth Circle or at Carol's Place in Underworld, but do not insult him when you first speak to him or he will not give you the quest. He gives you the task of finding and killing Dave (at the Republic of Dave), Ted Strayer (in Rivet City), Dukov (at Dukov's Place), and Allistair Tenpenny (at Tenpenny Tower). He says they are ghoul-haters, and he wants them each killed with a shot to the head (as zombies are killed in fiction). For that purpose, he will give the player a sniper rifle and five .308 caliber rounds. Crowley offers 100 caps per death by headshot with the sniper rifle as payment. He says that "word will get around" if Tenpenny is killed, but he wants proof for the others: "something personal... like a key or a ring."
 * Crowley will only pay 25 caps for any killing method other than a head shot, but you can lie about the act and get the full price by passing a somewhat difficult speech check. This does not apply to Tenpenny; he must be shot in the head by you to get the full reward, since word of his death would spread rather quickly.
 * Killing anybody grants you negative Karma although killing Tenpenny grants you positive Karma.

Crowley's true motives
Bribing or passing a speech check with any of the named non-player characters (excluding Charon) in Underworld—Ahzrukhal, Carol, Doctor Barrows, Winthrop, Patchwork, Tulip, or Quinn—will raise doubts about the targets' bigotry. Under questioning, Crowley will admit that he actually wants a special key from each target except Tenpenny. He still wants Tenpenny killed with a shot to the head. Instead of 100 caps per headshot, he will sweeten the deal by offering 100 caps up front plus an additional 100 caps for each key. Mister Crowley's objective is the suit of T-51b power armor still stored at Fort Constantine. You can learn about Fort Constantine and the power armor from Crowley (with a speech check). Other than the additional reward, the conditions of the quest do not change by learning this.

Tenpenny's counter offer
Tell Allistair Tenpenny that Crowley sent you to kill him. After a successful speech test, Tenpenny will offer 300 caps if you agree to kill Crowley instead.
 * Tenpenny pays 100 caps up front, so it is possible to double-cross him and just pocket the caps.
 * Killing Crowley and returning to Tenpenny for the reward ends the quest.

Getting the keys
The keys can be obtained by Speech checks, pickpocketing, or by looting the key from the owner's corpse. They may be collected in any order and can be delivered to Crowley one at a time or all at once.

Jeff Strayer is dead, but his son, Ted Strayer, is now in possession of his father's key. Ted lives in Rivet City.
 * Ted Strayer
 * Ted can be paid for his key.
 * He can be convinced with a Speech check.
 * He can be intimidated (Strength 6+ or Toughness perk).

Dukov can be found at Dukov's Place.
 * Dukov
 * Dukov can be paid for his key.
 * Female characters with the Black Widow perk can persuade him to give up the key.
 * Male characters with the Lady Killer perk can persuade Fantasia to get the key.
 * Cherry will retrieve the key if the player passes a Speech check and agrees to take her to Rivet City. The Speech check option appears only once. If you reject taking her to Rivet City you won't get the chance a second time.
 * With a successful Speech check, Dukov can be intimidated into giving up the key.

Dave can be found at the Republic of Dave.
 * Dave
 * With a Speech success, Dave will accept the player as a "Wasteland Ambassador" and present his key as a gift. He will also give you the key if you pass another speech check that is given if you failed the ambassador one.
 * After completing the unmarked quest Election Day in favor of either Rosie or Bob, you can take the key from his body in Old Olney.

Deliver the keys to Crowley
Kill Allistair Tenpenny and give Mister Crowley all three keys to collect your reward. He will then proceed to Fort Constantine to retrieve the armor. He will return to Underworld after a few days (provided he did not get killed in the Wasteland). At this point, one can kill him, which will turn all ghouls in Underworld hostile, or use reverse-pickpocketing in order to obtain the armor (he will be wearing it).
 * Reverse-pickpocketing will be difficult, because the armor has a DR of 50, one of the highest in the game.
 * Crowley may get stuck in bomb storage, even if he had all the keys. You need 100 lockpick skill to open the door.
 * Using the mesmetron (if successful) will turn him hostile, but everyone else will turn on him and kill him. This way, you can loot the armor off his body without angering the Underworld residents.

Retrieve the armor yourself
Proceed to Fort Constantine after obtaining the keys. Fort Constantine is located near the northern edge of the map, east-northeast of SatCom Array NW-05a and southeast of the train tunnel if The Pitt is installed. When you arrive at the fort you will encounter some Brotherhood of Steel Outcasts fighting protectrons and Mister Gutsies. Go to the small house labeled "CO Quarters," located downhill from Bomb Storage, and head downstairs. In the basement you will find a dead wastelander by an open safe. The door by the safe requires Strayer's key, and allows you access to the Launch Control Bunker. You can also grab the "Bobblehead - Big Guns" from the safe while you're there. Continue down the stairs towards Bomb Storage; you gain access here with Dukov's key. Inside the Bomb Storage facility, you will find Tara's body in front of a locked door. Open the door with Dave's key, proceed through the next door, disable the stasis field and take the T-51b power armor and T-51b power helmet.

There is a warhead storage key on Tara's body. It unlocks a door that's just up a set of steps from here. This leads to a large room where nuclear warheads are stored, and the area is consequently highly radioactive. This key also opens either of the Very Hard locked doors topside that lead to the Bomb Storage facility.

If you choose this solution, Mister Crowley can still be found in Carol's Place in the Underworld. He does not become hostile, but refuses to interact with the PC anymore, only repeating his line: "You stole what was rightfully mine..."

Deliver the keys to Crowley and retrieve the armor yourself
Kill Allistair Tenpenny and give Mister Crowley all three keys to collect your reward, then follow Crowley on his long journey to Fort Constantine. He will require a lot of protection from enemies in the Wasteland or else he will die along the way. Crowley will become hostile upon reaching Fort Constantine, at which point you can kill him to retrieve the keys. Or one can simply follow him into the lobby of the museum and kill him there (you will not lose any Karma).

If you don't want to follow Crowley, you can collect the keys (and kill Tenpenny), and then go directly to Fort Constantine. Clear the fort of enemies, open all the quest-related doors, but don't grab the armor. Then go to Underworld, give Crowley the keys to end the quest and collect your rewards, and finally fast travel back and grab the armor. Using this approach there is a possibility to come across a hostile Mr. Crowley at a random location in the wasteland, probably stalking the player for stealing "His" armor.


 * If you have Broken Steel installed, Crowley will glitch outside of the Museum of History and get stuck in a pillar after you give him the keys. You can fix this problem by waiting by the entrance and skipping 2 in-game hours. Crowley should appear at the entrance and proceed to Fort Constantine. If you have the Point Lookout add-on, then you can also fix this problem if you exit Underworld following Mr. Crowley with the double-barrel shotgun equipped and drawn, then when you arrive in the lobby, he will be there running towards the entrance to the Museum. You have to do the same when exiting the Museum. This may work with other weapons too (though it does not work with all weapons).

Completing the quest
The quest is marked as completed and the achievement/trophy given under any of the following conditions:
 * The player delivers the keys from Dukov, Ted Strayer, and Dave to Mr. Crowley.
 * The player acquires the power armor in Fort Constantine.
 * The player kills Crowley after having been hired by Tenpenny.
 * The player picks up (if previously dropped) or equips (themselves or their follower) the winterized T-51b power armor that was gained from the Anchorage Simulation (glitch).

Behind the scenes
A number of elements indicate that the Prototype Medic Power Armor was originally intended to be the armor recovered from Fort Constantine. The terminal for gaining access to the power armor lists it as "Medical Armor Prototype", while the EditorID for the Prototype Medic Power Armor is MS14PowerArmorMorphine, "MS14" being the internal EditorID of the quest.
 * The title is a reference to the common convention in zombie fiction that the undead can only be killed by destroying their brain. Mister Crowley himself refers to these legends. Allistair Tenpenny also mentions this if you tell him that Mr. Crowley is still alive.