So very long ago -
The Sole Survivor, General, Director, and Mother sat in a random chair at Sentinel Site. She was surrounded by the synths who she was going to kill to prevent their discovery as her accomplices in the biggest deception the Commonwealth ever rested its fate on.
Her only question, "What did I forget?"
Now-
"It's just the detail she forgot.", Valentine realized.
The Lone Wanderer glared at him, frustrated that the entirety of Reilly's Rangers could come up with nothing. "Mother Isolde forgot what?"
The synth shook his head and bent down over the white clad corpse. "Not Mother Isolde."
A single metal finger pointed to the white shining armor and suit the corpse wore.
"She just forgot that she's a woman out of time. She woke up in this world and saw that it was different while I've been living in post-war for so many years that I've seen how it's become different. Generally, everyone scouring their way through the apocalypse is way to impoverished to change fashion. Even the rich are just buying up what were expensive or classy clothes from before the war. But the Institute actually has the resources to modify what they wear. And these synths are dressed in the very latest fashion of Institute wear. While she would think that since everyone else' fashion has been stopped by the end of the world, so would the Institute's. Hell, no one would think of that - except me."
Valentine started to pick up speed."But why kill or destroy them? Any risk of contamination of coming to the Glowing Sea would have affected her as well, but she's been received back. The synths were shot in the head and then in the synth components. Now the synth components don't actually have a memory stores in them to the point where they're recoverable - so that's another clue. The person who shot these synths doesn't know a lot about synth engineering despite having access to knowing what there is to know about synths. But in taking out their brains she did show that she was paranoid about someone with enough tech to write and read memories itself from catching her."
Butcher walked between Reilly and the Lone Wanderer who had long been stunned into silence. "If you know who did this, then you need to say so. Now!"
Nick looked into his eyes. "Who did this? Who did this? Who had a career that would make her familiar with pre-war forensics so she could stage the scene? Who's the woman out of time enough to not cover up the synth's fashions being during her rule? Who's in cahoots with the Institute enough to get these synths out here in the first place?"
"If there was the slightest bit of evidence left to point to there actual killer, I'd have my doubts. But only one person would think to cover up their crimes this thoroughly - particularly when that crime was against the Institute. But if she's covering it up from the Institute then that means that even they don't know."
"I've got the bodies. I've got the means. I need opportunity and motive. When could the most recognizable person in the Commonwealth even attempt to do this? And why?"
Nick snapped his rubberized fingers, and started speaking into the Lone Wanderer's face like she knew what he was talking about. "The war. It's the result she needed. Right when she went on that 'failed' assassination mission!"
The Lone Wanderer grabbed the synth by the shoulders and shook him. "Who? Who Mr. Valentine? Who did this? We need to know so that we can turn them into the General's Minutemen to stop the Commonwealth-Capital Wastes War."
"It was the General. The General did this.", Nick told her.
Everyone of the Reilly's Rangers stopped milling around and closed in on him. "What did you say?", Charon demanded.
"She did this. The General was facing a protracted quagmire against the Gunners. She's got a pre-war education: she'd have to know that when war never ends, you eventually lose by wearing your army and country out. If she didn't overwhelmingly crush the Gunners, then she'd lose to the next foe. So she was desperate enough to do anything, including use the very same weapons that destroyed everything she ever knew. That was the motive.
"So she faked her authorization by declaring she was attempting to assassinate Colonel Cypress. She had wandered around the entirety of the Commonwealth and other territories before. And she had faced all sorts of monsters and organizations by herself. No one was surprised at the move and we were only surprised when she came back claiming failure because she never failed. With the only possible hanging question being her losing for once while everyone was involved with the investigation into how Gunner Palace got nuked, she had created the perfect opportunity.
"The means is obvious. She's the one that brought the Institute to heel. Of all the people she had access to, the Institute could decipher and use pre-war nuclear weaponry. Hence the synths and their current armor and clothing.
"The bodies. Here, Gunner Plaza, the ones she's going to rack up in the Capital Wastes if the Brotherhood of Steel doesn't get out of her way, the next war...If she's willing to use nuclear weaponry and just ban it for everyone else to...to...stay in character?"
The Lone Wanderer started commanding. "Alright. Now that we know this, we can expose her."
"No, we can't.", the detective warned.
"There's no finger prints other than the synths. There is a 10 MILLIMETER PISTOL that I'm nearly certain would have its ballistics match the wounds if studied just as much as I'm certain that we would find powder traces on one of the synths hands. And I'm certain because all of this was perfectly staged to make it look like a synth suicide mission by someone who is familiar with forensics."
"Forensics?", Reilly asked.
"The study of crime scenes and evidence.", the Lone Wanderer supplied from her Vault-Tec brand education.
"With no evidence, no one's going to believe you and they probably shouldn't. The Brotherhood of Steel sends a mercenary group to the Commonwealth and they just happen to accuse the General of the attack they're blamed for. Don't hear how that sounds? Even if you present the synth bodies she has two options. The first is a lie that's completely provable: she failed the assassination because her synths went rogue and she didn't know where, she didn't say they went rogue to avoid an anti-synth backlash in the middle of a war, she even covers with the Institute by not wanting to blame whatever for the bad programming. The second is also a lie but one that's completely believable: the Brotherhood of Steel are in so weak a position that they're fabricating this. Sending a group of mercenaries to jump synths when the Commonwealth just started offering them citizenship and the Capital Wastes still has anti-ghoul prejudices. The only way you knew of Sentinel Site is because the Brotherhood used it to nuke the Commonwealth. The war against the Capital Wastes needs to be finished because the Brotherhood is desperate, or at least desperate enough to try this lie."
"Her Pip-Boy!", the Lone Wanderer exclaimed.
"Good try.", Valentine lamented. "Her Pip-Boy has to be chipped and tracked by the Institute. And she certainly couldn't have made it out here without hers. So it would have to show that she was here when Sentinel Site was firing on Gunner Plaza. But on top of it being on the Generals' wrist, it's probably identical to one from Vault 88, which is near where the front lines were during the Commonwealth Civil War. I'd have switched it out for the time then, showing that I was on the front lines of the war - where the General said she was at - and then recovered it to show that my Pip-Boy was still chipped, even if I didn't know for fact that the Institute chipped it."
Brick demanded, "Then we force her to confess."
"And if you could then you would have assassinated her by now. Your showing on the Children of the Atom before we came here shows that.", the synth replied. "Besides, you think that the Commonwealth is going to turn against a woman who saved their asses, lost her son, and was tortured by the enemy she warned about?"
"We could trick her.", Brick said in a much softer voice.
"Because you're so much smarter than a woman who out competed everyone in school for two decades pre-war to become a lawyer? Or is it because you're so much smarter than the woman who did this to begin with?", Valentine challenged. "That's why you're grasping at straws now."
Reilly turned to the detective. "But you could tell them. How you figured it out. People would believe you."
"I'm a synth.", he replied. "Sure, an accepted one. But when Bob kills a child, Bob's word lets him walk versus whatever I have to say. I only get the Bobs of the world busted by finding the child before she's dead. Then the child's word is what gets Bob done in, not me.
"Wait, what's that?"
Everyone grew apprehensively silent. After a moment, they heard the sound interrupt the eerie quiet of the Glowing Sea.
"What now?"
