Nothing else attacks them on the way back, and they make it back upstairs and onto the roof without further incident. 

"We're home! Open up!" Amy calls once they get back to Nick's zeppelin.

Bots push the pair in and pile themselves in after and the zeppelin thunders into the sky before the door is even closed behind them.

"Woah- Jesus." Amy stumbles into the room, and grabs onto the closest fixed object to steady herself.

Edward falls into the wall, and just stays there. He does whimper slightly, but settles once the zeppelin slows.

"Rather speedy exit there. We got something on our tail I don't know about?"

"Raiders taking potshots at me every couple of minutes. Nothing heavy, but they could get lucky. Thus the hurry."

"Fair point."

Amy heads over to Edward and slumps next to him, already going through the information gleaned from Vault-tec. There's a few different Vaults she could try in the area, but she'd rather go back over this with James. He might have a better idea of where to start.

"Yep... There will be some turbulence as we avoid a radiation storm over New York. Aside from that, estimated travel time for Scrapheap Airlines flight zero zero one to Rivet City is five hours twenty minutes."

"Excellent. I will be recommending your service to my friends, which largely consist of Edward and that's probably it."

She retrieves some food from her pack, and after helping Edward eat some, she settles back down with her share.

The flight is quiet.

A robot drags the disabled synth into the workshop section at some point.

The synth is remarkably intact, it still has all of its plastic coverings. It would be easy to assume that the insides worked just fine still too. 

The mystery is, why did the secret Vault-tec basement lab have a synth?

Presumably because the goddamn Institute found the place and was using it for something or other. Or something. The secret basement wasn't that hard to find.

Maybe Vault-Tec invented synths, it wouldn't really surprise him at this point.

Anyway, he's here for the tech first and info second. But info is easier to get before you disassemble everything. He plugs in a terminal disconnected from other systems - security! - to try and pick apart the synth's memory.

The synth is reluctant to give up its secrets at first, firewalls slamming down with each hacking attempt, but it is an old enough model that persistent was enough to crack it. 

Once it has its secrets bared, Nick can note two major things. 1) that the synth was made in the last 30 years and 2) it ran away of its volition, from a shadowy organisation known only as the Institute. 

Yep, the Institute. There's only room for so many shadowy organizations, isn't there? Someone might pay for the information, though that's always tricky business. Still, one managed to rebel? Hmm... 

(Go away, squishy feelings.)

...He tries to see if the brain is irretrievably fried or if he could possibly disconnect the limb controls and boot it back up. He'd like to know more about that disabling cartridge Amy has anyway and an analysis will provide clues.

As he breaks through another firewall, some more snippets of information can be gleaned.
1) that it escaped just a week prior to Amy and the bots discovering it
2) that it wanted to be called 'Chester' and use male pronouns
3) it has a map of Boston hidden away, with a lantern symbol over one particular building

As for analysis of systems, Amy's weapon has fried the systems so they overloaded and the synth 'died', but all are intact and can be rebooted. Nick can try for a clean reboot to bring 'Chester' back, or wipe the memories away and be rewarded with a new bot to play with.

Hideout? Institute location? Treasure cache? Lantern: Possible Underground Railroad reference. Not enough information. And he's reluctant to throw himself into involvement with all this Institute stuff anyway.

New bots are always nice, but synths are creepy. And Chester here is already badly damaged.

He'll leave the brain for now, indecisive as usual, and play with some of the parts, trying to non-destructively glean any shiny tech secrets they might hold. He investigates the doodads from the rest of the building while he's at it.

They approach Rivet City.

The synth has no objections to tinkering. It is, after all, 'dead'.

Amy and Edward have moved to by the window, Amy sitting on the nearest bench, scrolling through her Pip-boy, with a furrow in her brow, but she seems quite content.

He doesn't even use the intercom this time! He comes through the bay door and says, "That electro-shock round or whatever it was is a nice toy, left that synth completely intact. I could probably even wake him up. Don't suppose I can buy some?"

"Thought you might like that. Very handy against bots, though the sentrybots can take a few rounds to go down." 

She slides off the workbench, and goes through her pack, pulling out a blue cartridge. "I'll give it to you in exchange for a favour," she says. She sounds like she already knows what she's going to ask for.

She's not one to underestimate or dismiss, he's learned that much. "The exchange rate on favors can get pretty bad, though our little expedition went well. Do expand on the services requested."

"Help James get Project Purity started again. You've got heaps of engineering expertise, we need that. James and Madison need all the help they can get. I know shit all about this stuff. I'm here to shoot at things that come too close."

She tosses the cartridge between her hands without looking.

"I do have heaps of engineering expertise. The problem with that favor, however, is that it is a very big favor, and one I have no way of knowing exactly how big it even is. I have no proper idea how difficult completing this project will be, what my prospective coworkers are like beyond a quick look at James, what opposition or interest I will attract - by the way, have you heard of The Institute?"

(Speaking in capital letters is an occasionally useful skill.)

"I get that you put your own skin first, Nick, I do. God knows I've had to do it a few times myself. But this is bigger than us. Bigger than anyone. This is a small step to making people better. Healthier. But if you don't want to, I won't stop you. You're right. I don't know what sort of opposition we will have. I guess I'm just willing to hope that people will see the value of this and leave us alone. I know it's naive, you don't have to tell me that."

She frowns. "I've heard of them, but they're whispered about like the bogeyman in Boston. Aside from that, no."

"I am now three standard deviations confident that they exist and are a credible threat if they decide to dislike you. They make synths, apparently. Are making, as of a couple weeks ago. Boston was mentioned a lot in those records."