It was a dense forest and the ground was covered in a light dusting of snow. Charley pulled her scarf further up her neck and stuffed her hands deep into her pockets. The Doctor walked a few feet away from the TARDIS onto a what looked like it might have been a path long ago. Fallen trees laid across its path and the forest had started to re-grow. He stood on the path for several moments looking in both directions.

"Which way?" Charley asked.

The Doctor sniffed the air. He licked a finger and held it up over his head, testing the winds. He looked down the path at his feet for any indication that someone had recently travelled the path in the snow. "This way," he announced and turned to the left. They made their way along the path. Charley had to jog to keep up with the Doctor's long strides. It wasn't long before the path began to climb. Charley's pace slowed as the climb became steeper.

The path turned and the path went steeper still. "Switchbacks. We're climbing a mountain, Charley."

Charley jumped over a log in the path's way, "Great!" she called and hurried along to keep up with the Doctor. With each turn of the switch backs, Charley's pace slowed. Her lungs started to ache.

"I think we are getting towards the top," the Doctor announced half an hour later. His stride had not slackened and he seemed completely unbothered by the cold temperature.

Charley was panting, "That's good," she gasped.

The Doctor turned around and saw Charley, red faced, and slowly walking towards him. He jogged back down the path to meet up with her. They sat down together in the middle of the path. Charley was taking deep breaths. The Doctor fished around in his pocket and pulled out a water pouch. He handed it to Charley, who eagerly took it.

"Not too fast, Charley," the Doctor said. He reached into another of his pockets and produced a breathing mask attached to a small metal container. "Hold this up to your face and take deep breaths."

Charley took the device from the Doctor and did as he told her. Immediately Charley felt better. Her head cleared and her lungs didn't feel like they were going to burst. The Doctor watched Charley' complexion return to its normal color. "Oxygen. The air on this mountain is quit thin, especially for someone who is use to living near sea-level." He watched as she took several more breaths. "Feeling better?"

Charley handed the mask back to the Doctor, "Right as rain, Doctor."

"Come on, we'll be at the top soon." He stood up, held out his hands and pulled Charley up. He took the rest of the climb a bit slower until they finally reached a level clearing. The sky above them was clear blue. A dying fire lay in the center of the clearing. Small wisps of black smoke still rose from the fire's embers. A heavy woven fabric was in a crumpled heap several feet away from the fire. The Doctor surveyed the scene. The marking in the ground told the Doctor that someone or something had recently been here, quite possibly scaring away the fire's keeper. "Judging by the markings on the ground, our distress caller was chased away from his fire before he was done. The way the smoke cloth is laying on the ground, I'd say the person was taken completely by surprise."

"I hope whoever it is, is alright," Charley said, gently picking up the cloth. It was a heavy fabric, grey in color, with heavily frayed edges. It smelled strongly of smoke.

"I hope so too, Charley. I hope so, too." The Doctor noticed the tracks led down another path. "Come on, let's follow their tracks." They started on the path on the other side of the clearing. Charley was pleased to realize this path did not climb more of the mountain. It twisted and turned through the woods, but stayed approximately at the same elevation. Charley, who was several paces behind the Doctor heard something in the trees behind her. She turned around and saw nothing.

Jogging up to the Doctor, she touched his shoulder and gave the velvet coat a slight tug. As quietly as she could she spoke into his ear, "I think we are being followed." She felt the Doctor's shoulder's stiffen under her grip, but he continued to walk casually down the path. His ears picked up on a slight noise.

"Get in front of me, Charley," he whispered. Charley obeyed and the moment she stepped in front of him, the Doctor spun around. His eyes caught sight of some movement in a bush alongside the path. He was there in three long strides, reached down into the bush, grabbed the follower and pulled him up.

Charley gasped.

"Don't hurt me, grownup!" A child dangled helplessly from the Doctor's strong grip.