"Looks like someone jammed the door open on this side," she replied, her torch beam swinging back and forth.
Coal was through a moment later and then it was my turn. It took me a few tries to actually pull myself up into the gap and eventually I had to grasp hold of one of the spokes to make it inside. It was very claustrophobic with the cool metal pressing against my hands and knees and the door above me just inches from my head.
I felt a mechanical vibration shudder through my palms and held my breath. Nothing else happened and I sped up. After a bit of shuffling, I made it through and dropped down on the far side.
Alicia's torch was illuminating the thing jamming the doors open. I stared at it for a while but couldn't make out what it had been; the crushing power of the doors had done a good job of rendering it unrecognisable.
"Well it's made of some kind of metal," Alicia shrugged.
"Why would someone jam it open?" I asked.
"Maybe they were trying to break in?" Alicia guessed.
"No, they were trying to make sure they could get out," Laurie said as she jumped down next to me. The doors let out a hollow groan and we all stepped away from them.
"What makes you think that?" I asked Laurie once the noise stopped.
"Mainly because they jammed it open from the inside."
"But why would the door be trying to lock with people down here?" I asked, shuddering.
"Maybe someone didn't want them getting out," Coal suggested.
"Why?"
"Who knows?" Alicia shrugged again.
"Maybe they didn't want them telling other people what had been going on down here," Laurie guessed.
"Whatever it was, I'm glad they got out," I said as I turned my torch to light the space ahead of us.
There was a short corridor filled with security monitors and scanners ahead of us. We had to walk through the various check points and guard stations to reach the other end.
We stepped through the derelict machinery first, passing some kind of control station which had a wall with a collection of ID badges hung along it. The badges had metallic strips along the bottom of them which we guessed meant they doubled as key cards.
Coal leant forwards, selected a badge with top level security and pocketed it.
Alicia had already moved on and was walking along an unmoving conveyor belt which passed through an X-ray machine and then a metal detector. As she moved under the latter, a loud bleeping sound filled the air momentarily.
A flurry of movement took place as the four of us snatched guns from holsters and flicked the safety catches off. Alicia stepped past the X-ray machine and the bleeping stopped.
"Okay, I feel stupid," Laurie said as she put her guns away again.
I laughed nervously as I followed suit. The bleeping repeated as the rest of us moved through but there were no other signs of there being any power switched on within the compound.
Beyond the security corridor we were lead up a short flight of stairs and entered a tunnel lined with doors on either side.
The doors, on closer inspection, hid little offices. They were laid out in a uniform pattern: each with desks, filing cabinets and old computers but nothing on the scale we were searching for.
The airlock on the outer door had kept the place free from dust and insects and the rooms felt strangely like they had been recently occupied. There were coffee mugs on desks beside family photos and papers spread out on some as if someone had recently been looking through them. Filing cabinets had open drawers adding to the feeling that the occupiers had just stepped into the next room and would be back at any moment.
But the deep silence proved that theory wrong. Our footsteps echoed in the empty space and the air hung still and heavy around us.
We checked behind every door but we knew there wasn't going to be anything different hidden within any of them. Eventually the corridor came to a junction but there were no signs to indicate which course we should take.
"Do we split up?" Laurie asked.
I glanced over my shoulder in the direction we had come from, feeling a chill on the back of my neck.