บท 51: The Astoria incident

As they approached the subway entrance, something caught Suzy's eye, and she quickly pulled Kevin back. "Hold up. Something's not right."

"What is it?" Kevin asked.

"I don't understand why the machines didn't try to breach that door. The subway entrance is right in front of their eyes. No attempts were made to conceal it." On hearing no reply from Kevin, she continued, "Subcity doesn't have any open entrances. You can only enter Subcity via one of the hatches. And they are all camouflaged. They do not stick out like this one here."

Kevin looked at the titanium door at the subway entrance. Suzy did have a valid point. This reinforced door was sticking out like a sore thumb in the middle of a ruined city. Though every building around the subway had been destroyed, there was not even a scratch on this door. 

"It's a titanium door. Perhaps the machines don't have enough firepower to breach it," Kevin guessed.