The Empty Man is one of companion Vicar Max’s optional side quests.
It involves him trying to find his inner self and become free of his obsession with the Plan and his faith in the whole subject.
This quest can actually be missed though, if you do not first recruit him to your team. To learn about how to recruit him see the link here: How To Recruit Vicar Max
After successfully recruiting him, it may then take a while before he starts asking if you can talk to him, thus again if you do not use him in your team or be around him during this then again this quest can be missed.
To complete the quest its actually straightforward and to my knowledge after testing it a few times, can only lead to one outcome too.
Thanks to the quest markers you cannot really get lost, just again be careful you do not miss the quest. Upon successfully completing the quest, you will obtain the Anything for a Friend trophy / achievement
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