This is set in the same universe, and with the same characters as Mountains, but I wouldn't really describe it as a sequel, much like End of Line and I, Borg.
This really shows the superhuman quality of Hanna (and Josh).
****
The large fan rotated slowly, moving the spoilt air out of the facility. It was chipped and scarred, and the air was stale. The girl cringed, before slipping through, away from the sunlight. Her blue eyes shone in the dark as she moved along the massive vent, which was slowly shrinking. By the time she got to the end, the fan was out of sight, so she turned on a head torch she had.
The brightness immediately blinded her, so she turned it off and used her senses instead. She could feel the vibration of feet in the pipe, so she moved onwards. She could hear talking, and moved closer; that would drown out the noise of her feet. She got to a junction a couple of meters down the pipe.
She could taste humid air to the left and followed it. It wasn't long before she got to a grid. She looked through and saw a toilet cubicle, with a man on it. She grinned before slowly, ever so slowly, removing the panel.
When it was gone, she dipped town behind the man's head and put her hands on his temples. Then, she twisted, feeling the sharp crack as his neck snapped. His body dropped off the toilet seat.
Silently, she lowered herself to the ground, before looking under the door. She was alone. She opened the door and slipped through it, locking it behind her. She ran to the exit door, hid behind it, before knocking. A guard outside said in Russian:
'You alright in there, Joe?' She smiled but remained silent.
'Joe?' The guard said again. She still remained silent, but this time pulled a knife from her belt. The guard sighed and opened the door. He walked through, closed it behind him without turning round, and walked towards the cubicles. He was halfway there when he noticed the girl just about to stab him. He never stood a chance.
The girl then walked out of the room, creeping along the ground. She looked left and right, and walked left. She sneaked like this for about 5 minutes, before coming up to a lone cell in the middle of a hanger.
There was a boy inside, with bright blue eyes like her. She looked at him, and he looked at her. He nodded, and the alarm went off...