Okay, I must admit, this quest is pretty fun.
First, go to Goodneighbor (Optional: Bring a companion that likes the “Violent” option to farm them, and don’t with people who dislike “Violent”). You go there for your main quest. Tune into Silver Shroud Radio. Once you follow the radio, talk to the guy. He wants you to go retrieve something. Have some weight open. (Note: if you already have the specific relic and optionally the others, you don’t have to do this) Travel to “Hubris Comics”, around the location of Swan’s Pond. There are three items that you can retrieve, along with an axe and costume. The axe is on the first floor and requires advanced lockpicking, while the costume is free, near the showroom. Ghouls await.
Once you retrieve the main relic, you can scram or stay for the extra loot. There’s also a magazine, so don’t leave w/o it. Go back to the guy. He upgrades the relic, and collects them for caps. Now he wants you to quest around, acting like someone. Equip the costume (it might not be the most protective, but whatever!), and walk around the place. Tune into the radio again, and find a bad guy. Do every possibly gosh-darn _______ as ______ option, because:
A: It’s fun.
B: It’s surprisingly effective.
Kill the guy. After that, walk around, and find the next. Continue that until you go to an apartment building. Once there, loot. You can do the optional objective, but most people aren’t fond of that. (Unless they’re a Super Mutant.) Find more people, and kill them. Eventually, you’ll have to go to a hospital. Go to the hospital, and go to an elevator. Remember to put on the costume before you enter, because if you don’t, a guy will die. That’s bad. Talk to him, and either:
A: Have firepower, and keep choosing the ______ as ______ options. Kill the person quickly before the person you’re trying to save dies.
B: Quicksave before every dialogue option, and volunteer to be killed first. Kill everyone, except for the person you’re saving.
(Some, like the Brotherhood’s companion, dislike you saving him)
After you’ve saved the person, talk to him. After you’re done, go back to Goodneighbor and talk to the mayor. He’ll give you money, and occasionally check back with the person you saved to give your armor improvements.
(Note: If you have completed the “Big Dig” quest and have the mayor as a companion, go with him, and then talk.)