Holy Water Walkthrough - Fallout 3 - Broken Steel

You pick up this quest by asking Scribe Bigsley about the problems with Megaton. Head over to Project Purity at the Jefferson Memorial. If Megaton has been destroyed, you can't get this quest.

Head to Megaton. Just outside the gate there is a water beggar. When you see him this time, however, you'll see a woman give him water. Unfortunately, he dies rather suddenly. Horrified, the woman will tell you where she got the water and then run off.

Apparently she got the water from the Holy Light Monastery over in Springvale. It's a quick walk from where you are. Head on over and you'll have no trouble finding the monastery. Or you can follow the woman as she runs off. She seems to flee right past the monastery.

When you reach the monestary you'll meet Brother Gerard. Before he will even speak with you he'll make you drink some 'Holy Water'. The only way you'll get in without a conflict is agreeing to be irradiated. So, shoot him liberally and take the key.

After you have the key,head over to the back left corner of the ruined building. You'll see a trap door in the corner that you can open with the key. Head on down. You won't immediately run into a conflict.

Once you're in the monastery you'll want to talk to Mother Curie III. There is a peaceful solution using the Charisma skill. But once you've found out what they are actually doing, which is trying to turn people into Ghouls, you just might want to cleanse the place. Be warned that there are some nastier ghouls in the basement.

After you've purged the place, head back to Scribe Bigsley. After you inform him of the situation and its resolution you'll get the quest complete notification.