Last time, I had just finished eeking out some justice to an amoral  scientist and blowing up a lot of ants.  Not wanting to go back through a  ton of caverns, I opt to take this strange tunnel exit I found with a  sign reading "Church Falls"
I walk up and find myself in the  middle of a fire-fight between.. well, someone who is firing a laser gun  and a butt load of Super Mutants.  Pretty soon, the Super Mutants are  charging me and.. make a long story short, I'm quickly carrying more  hunting rifles and boards with nails in them than I can manage.  Quick  sidetrip back to Megaton (No Moira - I STILL haven't gotten to Crabmen -  now give me my 8 bits for the board!) and I return to tell the orphan  that I've avenged his family.  He confirms that whatever the mad  scientist did to calm the ants wound up making them go crazy and start  killing each other.
Color me shocked.  Still, problem solved.  I  ask if there's anyplace he could go and he says his dad talked about  having a sister in Rivet City, but he has no idea where that is.   Neither do I.  Huh.
Ah well - no sense in putting it off anymore.  Time to die.
I  begin the death march toward the crab-man lair.  Amazingly, I have a  very peaceful time of it.  I run into a nice old lady with a shotgun  (she calls herself Grandma Sparkles) who tells me that she saw a group  of mercenaries who were looking for "some do-gooder from the Vault".   This can't possibly be good.  I also run into a group of ghouls trying  to find a place that will take them since they're having no luck finding  The Underground - a city run by ghouls, for ghouls.
Funny - in my real life and my virtual life - the most polite people are the freaks.
The  ghouls are actually standing right on top of the lair.  I quickly  abandon the stealthy approach for the time honored method of running  like mad, jumping down three stories into a pool of radioactive,  egg-infested water, planting the camera and then running like all the  demons in Hell are chasing after me - which was not too far from what  WAS chasing after me.
Still, I actually get a halfway decent  reward for this.  A hat!  A spiffy black fedora which has the neat  effect of boosting my stealth skill 5 points AND my perception by 1.   Oh, and some invisibility cloak device called The Stealth Boy, which I  haven't used yet as it only has four charges and I haven't run into any  missions (well, apart from this one) where stealth would be more useful  than running like hell or guns-a-blazing.
This job done, Moria  asks me to start work in the final chapter, which will be all about how  to rebuild society in the wake of Armageddon.  First task - go to Rivet  City (the most successful post-apoc town) and find out the history of  how they were founded.
Good news!  I now know how to get there  so I can track down the orphan's aunt.  Bad news!  It's ALLL the way  down in the SE corner of the world map and the closest place I can fast  travel to is... the spawning pool.
*sighs* At least I don't have  to go inside there.  I do, however, have to cross a radioactive river.   Luckily there's a shallow spot where I barely get wet running across.   Unfortunately, I wind up having to fight off two crabmen and a centaur.   There's also a few giant roaches but I avoid them.  Turns out they  don't bother me if I don't bother them and I don't have the ammo to  waste for a 2xp kill.
Getting across the river, I wind up  discovering the Tepid Sewers (the place Moria wanted me to go to find  giant mole rats... HA!) and someplace called Dukov's Place.  Dukov, it  turns out, is the most intelligent man I've met so far.  Rather than try  and eek out an honest living like all the other poor slobs, he has  renovated an entact government building into what is basically the  Playboy mansion and is now spending his days drinking, eating and  screwing the two ladies who are with him because - well, screwing an  odious Hugh Hefner wannabe with the voice of Lonod Mollari beats having  to do honest work.  At least, that's what one of them (Fantasia) thinks.   The other (Cherry) quickly bends to my Speechifying ways and agrees to  leave.... if I escort her to Rivet City.
Me: Great!  That's where I'm going anyway.
Cherry: Super.  But I'm not sleeping with you on the way there.
Me: Awwwwww!
Oh  well - here I am.  Wandering through the wilderness - weapon in my hand  and a redhead in a teddy at my side.  Why do I have the feeling I've  had this dream before?
Cherry goes running as we find a raider  camp.  Bad news is that - unlike most of the raiders I've seen so far -  these guys are smart enough to use guns.  Assault rifles even.  Good  news is that a raid of their camp and a looting of bodies after I end  them leaves me with so much loot, swag and excess weaponry I'd look  something like Jayne Cobb if my avatar reflected just how much crap I  was carrying at any given time.
I recover Cherry and keep heading  south.  Stumble across a Scavenger who seems like a might friendly guy.   We do some trading, he repairs my guns and I ask Cherry to stay put  while I scout ahead.
I wind up stumbling across a Super Mutant  camp right off the road.  Thankfully, I spot them way before they spot  me.  Actually, I spot their captive first and THEN the big green Hulking  guards.  Because apparently my ability to see hot redheads in need of  assistance is now extending into the game world.  I rescue her, gather  up more loot and then follow her to see where it is she is running off  to.
Surprisingly, it is ANOTHER Super Mutant Camp.  I follow  after the mysterious redhead, downing Supermutants all the while as I  run across this scaffolding.  It's dark, so I don't make out much of the  scenery, but I am suddenly informed that I am standing on the Jefferson  Memorial.  Cool.
I chase the redhead again until she  doubles-back almost all the way to where I left Cherry, taking a path  down another road.  Suddenly, she stops.  Won't say a word as I try to  talk to her.  I sense enemies close though.  Looking around I don't see  anything.... walk forward... and then I look up.  Catwalk above me, two  super mutants begin talking.  One complains of how he keeps trying to  remember their old life - they remember a woman - or maybe being a  woman.  Thinking hurts.  I cure this existential dilemma the only way I  know how.  Sniper rifle fire to the brainpan.
Following the road  and checking my map, I find myself close to the National History Museum  but see no obvious path there through the rubble.  I do, however, find a  bridge going back over the river.  Resolving to explore this later, I  go back to Cherry and - one more Super Mutant ambush later - we make our  way to Rivet City.
Rivet City is - it turns out - an entire city  built into the back half of a wrecked aircraft carrier.  I quickly  introduce myself to the lawman guarding the bridge and find out that  most of the decisions regarding the city are made by a Dr. Li.  I  resolve to go see her after I sell my excess loot.
Cherry  thanks me for everything but tells me not to get too big a head even  though "oh yay, you're my hero and everything."  But hey... another  Karma boost.  At this point, I don't think I can go any higher than Very  Good.
The market square does have everything - including a lot  of potential quest stuff that we're not going to mess with.  Why?  Well,  to be quite blunt, everyone in Rivet City is a jerkass.
*  There's tons of cops, but most of them are leaning on the walls and act  like it's a major imposition to even give me directions.
* The owners  of the local pharmacy are obviously sampling their own wears and nobody  seems to care that one of them is about to go over the edge.
*  Bannon, the fancy man who runs the clothing store AND represents the  merchants in the city council - makes it clear that he'd be very  grateful if someone found something incriminating in the quarters of the  head of the general store, who is challenging his seat.
* Angela,  one of the local teenage girls, is looking to score some ant pheromone  to try and win over Diego, a priest in training who loves her, but has  been convinced by the local priest that Angela is a test he must  overcome on the road to holiness.
* The town drunk is abusive to her  son, who everyone is convinced is a total brat.  Nobody seems to think  that - hey - given that his mom actively mocks him every chance she  gets, he has a good reason to be a hostile little smart-ass.
I  ignore all this - apart from asking everyone about the history of Rivet  City - finding out little more than Bannon claims to be responsible for  everything, most nobody else really cares and the old lady running the  bar tells me that a guy named Pinkerton - who is probably dead but if he  is still alive he's living on the far end of the ship- can tell me the  truth.
Stumbling around, I find a museum of sorts devoted to  American History.  Talking to the guy who runs it - Abraham Washington -  I find that he knows very little about the city history but he is in  need of a brave soul to break into the old National Archives - all in  the name of reclaiming the Declaration of Independence.  I agree to  help, simply because breaking in and entering is sort of my thing...  even if I am a Very Good agent of Law and Order.  Besides, apparently  the place is crawling with Super Mutants and they're always good for  loot.
I meet a woman who claims that this man named Sister is a  slave and that she's afraid he came for her.  Having little love for  slavery or slavers, I give her 25 bucks to buy herself a gun and decide  to deal with this guy.  Bad news - I find him at the inn and he doesn't  give me any good reason to have it out there.  Can't get the option to  say "Have at you you flesh-peddling scum!" or some such.  On the bright  side, the inn-keeper is the Orphan's aunt and she's more than happy to  take in her brother's son.
I also find the science lab and Dr.  Lee.  It turns out - hey - she knows my father and he was just here  trying to revive something called Project Purity.  Seems the whole  reason my dad was sneaking in and out of the Vault was to try and solve  the problem of cleaning up the toxic, radiation soaked water and that  he's gone back to his lab in... wait for it... The Jefferson Memorial to  work on it.
While in the lab, I also meet a jackass named  Zimmer, who comes from some big fancy town up north.  Seems they've  perfected the art of robotics to the point of creating realistic  androids.  One of them, apparently sick of being a slave, fled southward  and has apparently erased his own memories and had surgery to change  his features.  I nominally agree to help look for this android but  honestly... I'm going to seek this guy out to ask if I can help with  freeing the rest of his robotic brethren if only to spite this Zimmerman  jackass.      
Having talked to everyone in the city now, I go  off looking for this mysterious Pinkerton fellow.  Good news is that  the game quest journal will tell you where to go if you're not sure how  to find something.  Bad news is that... well, I think the thing is  bugged as the way it is showing me lies beyond that radioactive deadly  water.
For the first time since starting the game, I cheat a bit  and check out an on-line hint guide.  Seems I'm not alone and that  NOBODY knew how to find this guy.  Eventually, you can walk around and  find a metal walkway that leads to a door that requires a 100%  Lockpicking skill to bust open.  Or, you can just dive into the  radioactive water, swim through a tunnel into an underwater maze and  fight several Mirelurks in close-quarters while trying to get to the  same point.  Because, you know, it's totally logical that you'd go swim  around a radioactive lake full of mutant monsters looking for a tunnel  entrance that isn't on your map. :P
Regardless, I finally find  Pinkerton and he gives me the real truth on how Rivet Town was founded  as a scientific outpost and how he was the original founder, but he was  forced out of the city council and out of town by Dr. Li and her gang.   He gives me the notes that prove he is telling the truth, which I file  away to use for making certain jerkasses very uncomfortable later on.
So...  after swimming back through the same radioactive waste because the  jerkass won't unlock the door for me even though he no longer objects to  me coming to visit, I take a quick trip back to Megaton to tell Moira  the good news, get my next assignment (look for books at the Arlington  Virginia Library), sell more excess loot, stop off by the giant ant city  to tell the orphan he has a home and stop off by the Church Falls train  station (closest point to the library, which is where I want to go  next) where I discover that the things the Super Mutants were fighting,  which I didn't investigate in the dark, were apparently members of the  Brotherhood of Steel - i.e. the power-armor wearing Knights of the Round  Table wannabees well familiar to regulars of the Fallout series.
Man...  and I just got done selling excess loot.  Now I have to go back to  Megaton to sell these damn plasma cannons and power armor suits....