In the end, Lock did not confront Grisha immediately. The timing simply wasn't right.
For now, the Survey Corps couldn't act.
At that moment—inside the Survey Corps headquarters, in Commander Erwin Smith's office—
The air felt unusually still.
"Are you asking for leave again?" Erwin asked, his calm eyes sharpening with curiosity. "I'd like to know the reason."
"I have something I must do," Lock said, standing straight before him. His gaze didn't waver. "It's important."
Erwin studied him in silence for a moment, then nodded once.
"I see. In that case, go do what you must. Report to me the moment you return."
Lock bowed his head slightly. "Thank you, Commander."
As he turned to leave, he caught a glimpse of Captain Levi, who had remained silent the entire time, arms folded and expression unreadable. Lock met his eyes for a brief moment, then walked out, closing the office door behind him.
When the sound of footsteps faded, Levi finally spoke.
"You agreed too easily," he said flatly. "Why?"
"Why not?" Erwin replied calmly.
Levi frowned. "He's hiding something."
Erwin didn't deny it. Instead, he walked to the window, hands behind his back. "What did you think of what he proposed earlier?"
Levi paused, remembering Lock's earlier report. "A 'wise Titan,' huh? That's a bold idea."
"Indeed," Erwin said quietly. "For years, we believed Titans were mindless—driven only by instinct to devour humans. But the Colossal and Armored Titans' recent appearance… proved otherwise."
His tone deepened. "They appeared, attacked strategically, and then vanished. It's a serious contradiction to everything we thought we knew."
Levi's eyes narrowed. "You think they can think?"
Erwin turned from the window. "Why not? It's time we questioned our own assumptions."
Levi exhaled sharply. "Makes sense… but what about the other point?"
Erwin looked at him. Levi hesitated, recalling Lock's second theory. Even for him, it was almost too much to believe.
"You mean," Levi said slowly, "that Titans could be transformed humans?"
For a long moment, neither of them spoke.
Erwin's expression hardened, the faintest spark of dread crossing his otherwise composed face. "It's an outrageous thought. And yet… everything fits too perfectly."
Levi clenched his jaw. "Eyewitnesses said both the Colossal and Armored Titans disappeared without a trace. They didn't fly away. They didn't dig underground. There's only one explanation left."
He met Erwin's gaze.
"They're human."
Erwin nodded slightly. "It's a terrifying possibility—but a logical one."
"If that's true," Levi said darkly, "then those bastards are already inside the Walls."
Erwin's eyes glinted with that familiar fire—equal parts curiosity and conviction.
"Infiltrated… perhaps there are scenes beyond these Walls we can't yet imagine."
Levi scoffed, though a flicker of unease passed through him.
"Some scenes aren't worth seeing."
Outside, Lock walked across the courtyard, unaware—or perhaps perfectly aware—of the storm his words had stirred.
In his mind, a faint notification chimed—a reminder from the strange system that had guided him since awakening in this world. He dismissed it quickly, expression unreadable.
"They bought it," he thought, suppressing a smirk. "And why shouldn't they? Everything I said was true."
Those two "theories" he had presented weren't speculation—they were facts. But feeding them to Erwin at the right time was a move carefully calculated. He knew Erwin's mind well enough to predict his reaction: rational skepticism followed by deep curiosity.
If the Survey Corps could prepare earlier—if they could avoid the mistakes that would cost countless lives—then his plans would progress more smoothly. That was all that mattered.
Lock adjusted his maneuver gear and made his way back toward the residential block where Eren and the others had taken refuge.
It was a modest two-story house—once Lock's own—but now shared by several families displaced after Wall Maria's fall: Eren and his parents, Uncle Harry's family, and Lock himself.
The moment he opened the door, a heated argument filled the air.
"I said no, Eren!" Carla's voice trembled with both fear and anger. "You're not joining the Survey Corps!"
Eren's voice shot back, high with frustration. "But I have to! If we don't fight, we'll live like cattle forever!"
Lock paused in the doorway, leaning against the frame, an amused smile tugging at his lips. "Same argument every day," he muttered.
He slipped past them quietly and climbed the stairs to his room.
His quarters faced the one Grisha and Carla shared. From there, he could observe Grisha's movements whenever needed—something he had been doing for days now.
Grisha Yeager, doctor of high repute within the Walls, was a man both admired and quietly resented. His medical skill and knowledge gave him influence far beyond that of an ordinary citizen. Even now, after the fall of Wall Maria, when refugees flooded into Wall Rose territory, his services were in constant demand. Illness, injury, and fear hadn't lessened—they'd multiplied.
But Lock could tell something was off.
Grisha's behavior had changed. He was distracted. Restless. Often lost in thought.
Lock didn't need to guess why.
If Eren were ten years old now, then the time was drawing near—the time when Grisha would act, when he would seek out the Founding Titan from the Reiss family and pass the Attack Titan to his son.
Lock folded his arms and stared out the window, thinking.
He couldn't allow that to happen. Not yet.
If Grisha obtained the Founding Titan now, events would spiral uncontrollably. Lock needed time—time to position himself, to learn where the Reiss family hid, and to decide how best to take advantage of what was coming.
Besides, the Reiss family…
They disgusted him.
The true royal bloodline within the Walls—heirs to Karl Fritz's twisted ideal of "peace through ignorance." Bound by the Vow of Renunciation of War, they willingly condemned millions of Eldians to die quietly, generation after generation, believing it was atonement.
Frieda Reiss, the current Founding Titan, could have changed everything. She had the power, the authority, and the knowledge. But instead, she clung to the same hollow faith.
Lock scoffed quietly to himself.
"Sacrifice isn't nobility when it's forced," he thought. "It's cowardice disguised as mercy."
The Reiss family had become the very rot that paralyzed humanity within the Walls.
They didn't need salvation—they needed replacement.
And Lock intended to provide it.
He wasn't some naive soldier chasing dreams of freedom. He saw further than that. He understood the inevitability of conflict beyond the sea. The nations outside already had weapons that could crush Titans. Their technology was advancing faster than anyone here could imagine.
When the ships came—and they would come—no wall would save them.
Humanity couldn't hide forever behind stone and lies.
That was why he needed power.
Real power.
The Founding Titan, the Attack Titan, and perhaps even the Jaw Titan—each piece would bring him closer to what he needed: the strength to reshape this world before it collapsed.
He just needed patience.
And information.
Grisha was the key to both.
For now, Lock decided to remain quiet, to watch, and to wait for the perfect moment. Confrontation would come soon enough.
He leaned back against the chair, eyes drifting toward the ceiling as faint voices echoed downstairs—Carla's worried tone, Eren's muffled frustration, Mikasa's silence as she tried to calm them both.
A small, genuine smile tugged at his lips.
Despite everything, they were still just a family.
And for now, that was worth protecting.
But time was moving forward, and the world wouldn't wait for anyone—not even them.
The next morning, after a quiet breakfast, Grisha slipped out as usual, claiming to visit patients on the east side of town.
Lock's eyes followed him through the window until he disappeared around the corner.
He knew where Grisha was really going.
"Finally," Lock murmured, standing and reaching for his blades. "It's time to see where your faith leads you, Doctor."
With a quick adjustment of his maneuver gear, he stepped out onto the roof, sunlight glinting off his blades as he took to the air—
a silent shadow trailing after the man who held the key to humanity's future.
---
A/N: Advanced Chapters Available on Patreon
Support: patreon.com/Narrator_San