'...The rocks are vibrating. Gently. Just gently.' He hesitated for a moment. 'We can't be sure whatever is in here is the reason for the men disappearing. We don't know if they've been captured. It becomes tricky when... Different creatures are involved. They could be prisoners, they could still be alive, just lost in the caves, or they may not even be of this time any longer. You're assuming.'<br/>Another pause as he pressed his head to the rock.<br/>'Though, granted, it usually does end up being the hostile explanation. Peace, Isabel, is a mere illusion. And these rocks are definitely vibrating.'<br/><br/>Vibrating rocks meant machinery.<br/><br/>But how was it running...?