Reformation

 is a quest in the Fallout 4 add-on Far Harbor.

Quick walkthrough

 * Recover Martin's holotapes
 * Give Martin's holotapes to DiMA
 * Convince the High Confessor to meet with you
 * Play "Martin's new age"(holotape) to High Confessor
 * Head to the meeting location
 * Deal with the High Confessor
 * Hide the evidence
 * Return to DiMA

Detailed walkthrough
During the quest The Way Life Should Be when confronting DiMA about killing and replacing Captain Avery, the Sole Survivor can agree to keep it secret. After that DiMA will suggest to the Sole Survivor a plan about replacing High Confessor Thektus with a synth to make peace between the factions. Agreeing to the plan will start the quest. The Sole Survivor then has to find old High Confessor Martin's holotapes and bring them back to DiMA. The Survivor will then go talk to Thektus and assure that the old confessor Martin is going to come back and take over his position by showing him a faked holotape from Martin, the Survivor will then meet Thektus in the command center and kill him. Alternatively, the Sole Survivor can pass a medium speech check to make him flee. The Sole Survivor then returns to Acadia and sees DiMA talking with the new synth High Confessor. DiMa will reward the Survivor with 1500 caps and Protector of Arcadia perk. Sole Survivor will then get miscellaneous quest Speak to High Confessor, which will reward the player with Atom's Bulwark. Additionally the Survivor can return to Far Harbor and witness a meeting of the townsfolk, where Avery informs everyone that they have made peace with Children of Atom. Avery will give survivor 1500 caps when talking to her.