Fugaku was no fool.
The moment he heard his father's words, he immediately understood the old man's plan — he intended to use Mikoto to lure Kushina, the Nine-Tails' jinchūriki, out and capture her.
Realizing this, Fugaku grew frantic. He and Mikoto had been childhood sweethearts, and his love for her ran deep — down to his very bones.
And now his father wanted to use her as bait in such a cruel scheme? How could he possibly allow that?
"Father, how can you do this? You know Mikoto's personality — sending her to do this is no different from sending her to her death!"
At those words, the faint smile on Yamashiro's face vanished.
He suddenly slapped Fugaku hard across the face, then seized him by the collar and roared:
"My dear son, let me teach you one final lesson.
This lesson is called — For the success of a great plan, any person or thing that stands in the way can be sacrificed."
As he spoke, Yamashiro's pupils began to twist and change — transforming into a complex, sinister pattern that Fugaku had never seen before.
Fugaku stared, utterly shocked.
That was… the Mangekyō Sharingan!
But his father had never awakened the Mangekyō.
If it had suddenly appeared, there was only one explanation — he must have transplanted the eyes of one of their ancestors.
As clan head, Fugaku knew secrets that few others did — such as the darkest chapter of Uchiha history.
Long ago, the Uchiha had developed a forbidden technique called Izanagi.
Its abuse had led to a devastating civil war among the clan.
During that conflict, many awakened the Mangekyō Sharingan — and just as many perished.
It was only when a powerful kunoichi named Uchiha Naori created a counter-technique called Izanami that the chaos was finally brought to an end.
This period of shame had since been erased from public record, sealed away by successive clan heads.
The Mangekyō eyes left behind from that era had been secretly preserved — kept as the Uchiha's ultimate trump card.
Because only the clan heads knew this secret, most Uchiha believed that only Madara and Izuna had ever awakened the Mangekyō.
And now, seeing the truth before him, Fugaku realized — his father must have transplanted one of those ancient eyes.
While Fugaku was still reeling in shock, Yamashiro finished rousing the clan with his fiery rhetoric.
No matter what happened tonight, rebellion was inevitable.
Once the clansmen dispersed, Yamashiro helped his son up and said quietly:
"You may resent my decision, but believe me — everything I've done is for the sake of the Uchiha… and for your sake."
But Fugaku violently slapped his father's hand away and shouted:
"If you truly cared about me, you wouldn't make Mikoto do something like this!"
Yamashiro's expression darkened. His voice was cold.
"I already told you — for the success of the plan, some sacrifices are necessary."
This time, Fugaku did not yield.
He took a defensive stance, his Sharingan spinning — three tomoe blazing to life.
"Father, no matter what happens, I'll stop you!
If you truly care about me, you won't force Mikoto into this.
I won't help you convince her — and on this matter, there is absolutely no room for discussion!"
"No room for discussion?"
Yamashiro turned back toward his son. The Mangekyō spun in his eyes, its strange pattern glowing ominously.
The instant Fugaku saw it, his body froze in place.
In a flash, Yamashiro moved — faster than lightning — and appeared behind Fugaku.
A sharp chop struck the back of his son's neck.
Fugaku had never imagined that his dying father could move with such speed.
Even as he struggled to break free of the genjutsu, darkness consumed him, and he collapsed unconscious.
As his awareness faded, realization dawned on him.
His father's sudden surge of power… it had to be the result of the Uchiha clan's secret medicine — a dangerous drug that temporarily enhanced one's genjutsu and strengthened the body.
Its effects were powerful — but the cost was enormous.
The user's lifespan would be drastically shortened.
His father, already on death's doorstep, had chosen to take such a drug.
Clearly, he had no intention of living much longer.
Perhaps his father truly believed this was all "for his sake."
And perhaps, when he spoke of "necessary sacrifices"…
he hadn't been referring to Mikoto alone.
...
When Fugaku fell to the floor, Yamashiro looked down at him and sighed deeply.
He said nothing more.
Silently, the old man turned and left the Naka Shrine — disappearing into the night as he made his way back home.
Mikoto had long since grown impatient waiting at home for her husband and father-in-law to return.
When she finally heard the door open, she hurriedly stepped outside and called out:
"Father-in-law, you're back! Where's Fugaku? Weren't you two together—"
But before she could finish her sentence, her gaze met a pair of strange, sinister eyes.
Her expression went blank and her movements froze — it was clear she had fallen into a genjutsu.
After completing this, Yamashiro slowly collapsed to the floor, clutching his chest and gasping for breath.
"The final preparations are complete. Now we just wait for tonight."
Completely exhausted, he didn't notice how unnaturally quiet the house had become — nor did he realize that his little grandson still hadn't come home.
...
Inside the Hokage's Office
Tsunade sat at her desk, looking across at Itachi, who sitting on the chair could barely peer over the top with half his head, and said:
"So," she said,
"you're telling me that your grandfather and father are plotting a rebellion —
and that they may even attack the Hokage building soon?"
Itachi nodded nervously, his small hands clenched in his lap.
Tsunade's lips curled into a faint smile.
"Alright, I understand.
Thank you for coming forward and warning me — I'll make sure we're prepared and do everything possible to prevent this conflict.
And for what you've done today, I promise you this: I'll spare the lives of your father and grandfather.
Keep working hard, Itachi. One day, you'll become as strong as Kuugetsu."
Hearing this, the tension on Itachi's face finally eased, and a faint smile appeared.
He hopped off his chair, bowed deeply, and said:
"Thank you, Lady Tsunade!
I'll train hard — I'll definitely resolve the conflict between our clan and Konoha. I promise!"
Then he turned to Shisui and tugged at his sleeve.
"Come on, Big Brother Shisui, we have to go back.
If Father or Grandfather find out we were gone too long, we'll be in trouble!"
The two of them hurriedly said their goodbyes and left.
Tsunade watched the two little figures disappear through the door, then signaled for two ANBU operatives to secretly escort them home.
Once the room fell silent again, her smile faded.
She turned to Kuugetsu and asked quietly:
"Can we confirm this information is reliable?"
When Kuugetsu nodded, Tsunade immediately issued her orders:
"Shikaku, pass down my command —
No ANBU are to rest tonight. Everyone will remain on standby in secret,
but the visible guard posts are to remain unchanged.
Send word to Hoshiyomi and Minato immediately — tell them to return at once.
Lastly, deploy three squads near the Uzumaki compound.
No matter what, Kushina's safety must be guaranteed. Kushina's security absolutely must not be compromised!"
(Author's note)
I feel that making Yamashiro this kind of character best fits the Naruto-style antagonist and the Uchiha archetype — unyielding, ruthless, but guided by conviction and a willingness to sacrifice everything for his ideals.
This, I think, is the truest essence of what it means to be an Uchiha.