Ghost had gone through enough trauma to know the inside of his own head. Every shadow and memory. The very cracks in the walls he built to keep the world out. His mind was a fortress of locked doors and dim corridors where only he walked. Where only he was supposed to walk.

So when he first heard a voice humming behind the walls of his consciousness he froze in the middle of cleaning his rifle. The sound was soft and unfamiliar. Not tinnitus. Not a memory. Not madness that he would recognize.

It was someone else.

A stranger? In his own mind? Or had Ghost finally crossed the line of insanity.

He stopped breathing. Forced himself to listen again. Nothing. Silence returned as if the world had swallowed all sound. Ghost chalked it up to exhaustion. The lack of sleep or too many days in the field.

Until the second time.

He woke in the barracks sometime before dawn. Sweat on his chest. Breath caught in his throat. A whisper lingered in his ear even though no one else was there.

“You should get up. It is not safe here.”

Ghost reached for his knife within seconds. The blade familiar in his fist. His heart hammered as if bracing for an ambush.

But again, silence.

He sat there in the dark and for the first time in years his hands trembled. Not from fear of an enemy soldier. But from something stranger than any battlefield.

The voice stayed. It drifted in and out throughout the days that followed. Sometimes curious. Sometimes quiet. Sometimes so close it felt like someone was leaning over his shoulder.

Ghost tried to ignore it. He tried to shut it out. He tried to convince himself that it was nothing.

But the voice was patient.

By the fourth day it felt like two sparks sharing the same skull. A second presence pressed lightly against his thoughts. Not violent. Not intrusive. Just there. Breathing when he breathed. Observing everything through his eyes.

Ghost stood alone in the locker room after a mission and stared at his reflection. The mask looked back. His own thoughts felt crowded with the pressnce lingering in his skull. His jaw clenched. The decision made to finally confront whoever had...well...invaded his mind.

“Tell me,” he murmured under his breath. “What the hell are you.”