How to unlock: You must complete the Institutionalized main quest while you're in the Institute (M5,6) and you must agree to cooperate with this faction during your first conversation with Father.
- Talk to Father
- Meet with the Courser
- Reclaim the synth that escaped
- Return to Father
- Go to your quarter
Meeting with the Courser
At the start of the quest find the Father while you're in the Institute. Talk with him and you will receive a task about finding and bringing back a synth that escaped. You can leave the Institute now. The synth you are looking for can be found in the location called Libertalia (eastern part of the world map). Before going there, first you must meet with a Courser that will help you in finding the target. In order to do it, go (or use quick travel) to the Nahant's sheriff department location that can be found slightly north from Libertalia. There you must locate the X6-88 courser and speak with him.
Reclaiming the synth who escaped
Pretty strong raiders can be found in the Libertalia, it is a good idea to attack them from surprise. Use a sniper rifle or any other weapon that is effective from long distance. The location can be explored in two main ways - by walking through the narrow platforms that lead to other boats or by swimming to the positions occupied by new bandits. In the second case you must of course remember that the water is radioactive, so you will have to use RadAway (and optionally Rad-X).
The synth you seek can be found on the deck of a giant half sunken tanker which can be found most far to the south in Libertalia. You can get to the deck of the unit in two main ways - by using the travel platform to ride to the tanker or by swimming to it. Before you decide how to get to the tanker, first use some good sniper weapon to eliminate as many enemies as possible from safe distance. It is a very important matter, as one of the enemies has Fat Man and you can easily die during a more direct confrontation - all he needs to do is shoot the mini atom bomb at you.
Once you get to the deck of the tanker, start going to its upper decks. You must find the door that lead to the captain's quarter. Use it and once you reach the new location, listen to the short conversation with X6-88. You will receive codes needed for resetting the synth. Now you can plunder the room or immediately use the upper hatch that leads to the highest deck of the tanker.
Walk towards Gabriel, the rebel synth. During the conversation you can use the code you received before and reset Gabriel (the left dialogue option). If you do it, you will be teleported to the Institute. Optionally, you can provoke a battle. It isn't possible to completely avoid the battle, but depending on your actions you will have to defeat only two of Gabriel's followers or a set of three enemies.
Return to the Institute
You can search the highest deck of the tanker or teleport immediately to the Institute. Go meet the Father. He will be satisfied with the outcome no matter whether you destroyed or reset the rebel synth. The Father will also inform you that you have received a quarter in the Institute (you can sleep there and find some basic supplies). Go to it in order to complete the first major quest for this faction.
Quest rewards: Experience points, new Institute quest (The Battle of Bunker Hill), your own quarter in the Institute.