Blind Betrayal

Blind Betrayal is both a quest and achievement/trophy in Fallout 4.

Synopsis
As the Brotherhood of Steel finds itself on the verge of success in their Commonwealth invasion, a startling discovery is made of one of their own. A paladin that was considered one of their best, has a secret, and now a hard decision needs to made for their future.

Walkthrough

 * 1) Elder Maxson will require the Sole Survivor's presence, in which he will reveal that Paladin Danse has been identified as a runaway synth. The elder will send the Sole Survivor on a mission to eliminate this newly identified threat, which opens up the Sole Survivor to a myriad of options.
 * 2) After speaking to Proctor Quinlan and then Scribe Haylen, it is revealed that Danse can be tracked through his power armor, which leads to the Sole Survivor to Listening post Bravo, where they are forced to deal with a moderate number of hostile turrets and protectrons.
 * 3) Taking an elevator down into the depths of the listening post, and dealing with any encountered security, the Sole Survivor will inevitably encounter Paladin Danse. At this point, the Sole Survivor may:
 * 4) Kill Danse immediately, in which his holotags will need to be returned to Elder Maxson.
 * 5) Fail to persuade Danse, in which he will give the Sole Survivor an order to give his holotags to Elder Maxson, and tell him that Danse is dead.
 * 6) Succeed to persuade Danse, in which he will come along peacefully, showing that his true colors do not fly with the Institute.
 * 7) Should Danse hand over his tags peacefully, the party will be interrupted as they exit the listening post, and either convince the interrupting party to let Danse live, or allow for them to kill Danse in the Sole Survivor's stead.
 * 8) Regardless of the Sole Survivor's actions at the listening post, they will need to return to Elder Maxson with Danse's tags, in which Danse is removed as a member of the BoS, and the Sole Survivor is promoted to the rank of paladin.