Following the transmission lines discovered in the surveillance room, Carl and her men eventually lifted a hatch connected to the roof and emerged onto the top floor.
At the edge of the rooftop, they spotted a signal transmitter. The moment they saw it, one of the experienced subordinates told Carl about the device's origin and purpose.
"Lord Karl, this is an old-style signal transmitter. It can transmit UHF signals over short distances. The signal can't be intercepted, but it can only be transmitted within line of sight. The place receiving the signal may be somewhere we can see."
The experienced subordinate crouched beside the device, running his fingers over its rusted casing as though checking something. Carl studied the bulky, rust-covered machine, nearly twice a person's height, and gave a slight nod. "So we need to search for the receiving point nearby?"
She looked over the forest of skyscrapers around them—among so many tall buildings, there were countless places that fell within "line of sight." By the time they checked them one by one, the target would have vanished without a trace.
Was the trail going to end here?
Just as Carl felt a pang of regret, the subordinate suddenly spoke. "Lord Karl, I've already pinpointed the approximate location of their signal receiver."
"So soon?" Carl was somewhat surprised.
Every building in the entire block was within sight. This subordinate's efficiency was almost too high.
Noticing Carl's confusion, the subordinate explained while rapidly operating the detection equipment, "Militech used this back then. It's an old piece of equipment, more than fifty years old. It may be ancient, but our training specifically covered devices like this."
His fingertip tapped an inconspicuous port on the side of the device. "This equipment has a critical flaw. Its transmission signal can't be intercepted, but