Deacon

"Deacon" is a Railroad agent living in the Commonwealth in 2287, and a potential companion of the Sole Survivor.

Background
Little is known about his past prior to joining the Railroad, which he admits he is dishonest about. He states that he was among the first liberated Gen 3's, that he helped found the Railroad, and that he is the true leader of the organization with Desdemona serving as a figurehead. Desdemona suspects that he and "John D." are one in the same.

He shares that when he was younger, he was a member of the University Point (UP) Deathclaws, a gang that harassed people accused of being synths. Their antagonism escalated to the lynching of a man suspected of being a Gen 3. Shaken by his part in the murder, Deacon left the gang to settle down as a farmer. Sometime later he married a woman named Barbara. They intended to start a family, but the UP Deathclaws reemerged and attacked the farm. The gang somehow had learned - to both Deacon's and Barbara's surprise - that Barbara was a synth. Deacon killed the gang members in retaliation.

Work with the Railroad
He was subsequently contacted by the Railroad, who was unaware of his prior affiliation with the gang. Despite believing himself undeserving, Deacon swore himself to their cause. He took the name "Deacon" and survived an Institute raid on the Railroad, with Pinky Thompson attributing the organization's survival to his escape plan. When Pinky stepped down in 2277, he aided Doctor Carrington and Desdemona in revising the organization's policies to put a focus on operational security.

Deacon became one of Desdemona's top men, carrying out important missions and escorting synths of high value for the Railroad. Most of his work undercover has been tracking persons of interest. When the Sole Survivor awakens from cryostasis inside Vault 111 and emerges into the area, Deacon takes an interest in the traveler. He shadows them throughout the Commonwealth in order to gather information on their activities, with the hopes of recruiting them for the organization in a time of crisis.

Quests

 * Tradecraft: Deacon accompanies the Sole Survivor to the Railroad's previous headquarters to retrieve a lost prototype.
 * Precipice of War: The Sole Survivor and Deacon escort Tinker Tom to Cambridge Police Station to steal a Brotherhood vertibird.
 * Rockets' Red Glare: Using the stolen vertibird, the Sole Survivor and Deacon infiltrate and sabotage the Prydwen.
 * The Nuclear Option: Deacon and the other members of the Railroad assault the Institute, freeing the synths within before blowing up the facility's nuclear reactor.
 * Tactical Thinking, End of the Line: The Sole Survivor is dispatched to kill the Railroad's leaders, including Deacon.

Effects of player's actions

 * When the Sole Survivor first approaches the group, Deacon vouches for the Sole Survivor. He can cite many of the Sole Survivor's accomplishments and past actions to introduce them to Desdemona. Should the Sole Survivor agree to join up, Deacon will offer his services as a companion.
 * The amount of actions that Deacon can comment on is varied, such as taking out Sinjin, being a member of the Brotherhood of Steel, serving as general of the Commonwealth Minutemen, and other notable achievements. If the player meets The Railroad before these events, Deacon will make the remark, "Someone even being able to spell 'Railroad' is a cause for celebration these days" instead of noting any major events.
 * At maximum approval Deacon awards the Cloak & Dagger perk, which gives +40% duration for Stealth Boys and +20% damage from sneak attacks.
 * Deacon will become instantly hostile if the player character kills a settler or anyone involved in the Railroad.
 * Siding with the Brotherhood of Steel or the Institute in the endgame sequence will flag the player character an enemy of the Railroad, resulting in the loss of Deacon as a companion and turning him hostile.
 * After siding with the Minutemen and finishing the end game sequence without completing the optional quest, the Railroad and Deacon will turn hostile when the player character next speaks to Desdemona. They may still speak to other Railroad characters and complete quests for them.

Appearances
Deacon appears only in Fallout 4.

Behind the scenes

 * Ryan Alosio, Deacon's voice actor, has expressed interest in reprising his role as Deacon in future installments, and often shares fan-created content related to Deacon on his social media.
 * Deacon's dialogue contains nods to previous Fallout games. These include suggesting "Code Violet" as a team name (part of Harkness' override code in Fallout 3), attempting to use what he says is Robert House's personal override codes on Deezer (he claims to have won it in a poker game), and joking about wanting to convince a new recruit he is actually John Henry Eden.