When the Doctor sprinted away, Robin followed immediately. This time, there was no hesitation, no thoughts, just following. She had to see what was inside; she had to know what he was up to; she had to be part of this event that was so sure to be amazing.<br/><br/>"The puzzle sounded appealing and everything," she said as they entered the cave, "But I figured I might as well come with you." But she stopped talking as the darkness enveloped them, and gulped when she caught sight of the strange things hanging from the walls. It was with great relief that she saw the way ahead was illuminated by some sort of weird, green light.<br/><br/>The orbs were fascinating, unlike anything she had seen before. But then again, she was in a cave at the bottom of an impossibly huge tree, trying to stop an army of creatures that had survived despite countless attempts on their destruction. So she supposed a couple of orbs filled with an unwavering green light were probably the<em>least</em>strange things she had seen since meeting the Doctor.<br/><br/>As he spoke again, she listened with interest. The beeping in her head was growing louder, but her ability to tune it out was growing stronger at the same time.<br/><br/>"Well," she said as he finished, "When you have eliminated the impossible, whatever remains, however improbable, must be the truth. So, what's this story you're talking about?"