The Doctor and Rose set off at first light. The storm had passed, but the snow was much deeper than it had been yesterday, which made their way difficult. The Doctor spent a lot of time studying the hole in the fence.

"I think they went… that way," he said, pointing to the east. He pulled something out of his coat pocket and swung it in an arch in front of him. It was beeping quietly.

"What's that?" Rose asked.

"It's a... well… let's just say it's a Jack detector." The beeping grew louder and more persistent. "Come on!" The Doctor took off in the direction of the beeping, Rose at his heels. They hiked for quite some time, but not as long as it had taken them to get to the base from the TARDIS. The previous day felt like ages ago to Rose.

"We'll find him," said the Doctor, answering her unasked question. "He'll be fine." Rose bit her lip.

Suddenly, the Doctor stopped and pointed. "There," he whispered, pulling Rose down behind a snow bank. "That cave. I think he must be in there."

"And what about the Yeti? Is it in there, too?"

"Well, we'll just have to find out, won't we?" He crept out from behind the snow bank and darted toward the cave. Rose followed.

Tentatively, they peered into the entrance. There was no sign of the creature, and lying sprawled about twenty feet from the entrance was Jack. They both sprinted to his side.

"Jack," said Rose tentatively, touching his shoulder. Jack groaned.

"Don't try to move," said the Doctor, kneeling beside him. "We're here." He placed a hand on Jack's forehead. "What happened?"

"It grabbed me and dragged me off," he said, as the Doctor eased him into a sitting position. Rose slipped an arm around his waist. "I was out for a couple hours, did a number on my head. I must have some lump."

The Doctor gently touched the back of Jack's head. Rose thought she caught a brief look of grim resignation flash across his face.

"How is it, Doc?" Jack asked wryly.

The Doctor ruffled Jack's hair and pressed a kiss to his temple. "You'll live," he said.

"Have you seen it since?" Rose asked.

Jack frowned. "I don't really remember," he murmured. "It came back after I woke up–I ran some scans. This place is full of radiation. It's like a cyclical reactor!" He began tapping buttons on his wrist unit and showed the readout to the Doctor. The Doctor frowned and took out his sonic screwdriver.

"Jack, try to remember, what did it do when you woke up?"

Jack frowned. "It looked at me." He gave an involuntary shudder. "That's all I remember–it looked at me." He shook his head. "I saw something. It was an illusion, it must be some kind of telepath." Gripping the wall of the cave, he pulled himself to his feet. "Let's get out of here. I don't want to be around when it comes back."

"Don't move too fast," said the Doctor quickly. "Your brain's just had the shock of its life. Synapses firing like mad. Now tell me. What did you see?"

Jack shook his head. "It doesn't matter. Come on." Leaning on the Doctor and Rose, Jack was able to hobble toward the mouth of the cave. They were nearly outside when a shadow fell over them.

"Ah, crap," muttered Jack.

"Don't look at it!" shouted the Doctor. His voice seemed very far away… fading… falling.

Lonely, so lonely. She would never be happy again. They hated her–Jack and the Doctor. They didn't need her; they had each other. She was just slowing them down, with her twenty-first century stupidity. And even if she went home, her mother and Mickey wouldn't take her back; she'd been too many places and seen too much. She was trapped between two worlds, not welcome in either. All she wanted to do was die.

"Rose!" The Doctor's voice was suddenly close. He jammed his sunglasses onto her face. "Stay with me, Rose. Don't look at it!"

Rose blinked. The Yeti was standing before them, but Rose felt… nothing. She reached up to touch the sunglasses.

"Keep those on," said the Doctor urgently. "The lenses, they're made of an argon composite. It dampers the psychic field." He tightened his grip on Jack's shoulders, pressing him to him. "Don't look," he repeated. "What you saw before, that was how it hunts. It's a sympath."

"A what?" asked Jack, his voice muffled by the Doctor's coat.

"A sympath."

"Why isn't it bothering you?" asked Rose.

"Because it's not adjusted to me. It thinks I'm human, so it's hitting me with human wavelengths. I feel it, but not as strongly as you two. Now, come on. Let's get out of here before it figures out."

"It's not going to chase us?" asked Rose, as they stumbled out of the cave.

"Not if I do this." The Doctor whirled, and pointed the sonic screwdriver at the cave. An earsplitting whine filled the air, causing Jack and Rose to cover their ears. The rocks, snow and dirt above the cave trembled and then fell, raining down on the entrance. "That should buy us some time. Now, run!" The Doctor and Rose grabbed Jack and hurried away from the cave as fast as they could. It was exhausting supporting him, but they moved faster the more strength Jack regained.

"So I take it that's not really the Yeti?" asked Jack.

"Well." The Doctor shrugged. "It is the Yeti, in a way. But it's really a sympath–a Dondolarian."

"A Dondolarian?" Jack looked bewildered. "I thought those were a myth."

"Funny coincidence–you thought the Yeti was a myth, too."

Jack scowled. "So that means it was trying to kill us."

"Wait, hold on," said Rose. "What's a Dondo-whatever?"

"Dondolarian. It's a sympath. That's the opposite of an empath. Instead of feeding on other peoples' emotions, a sympath feeds on offloading their emotions onto others. Imagine if every emotion you ever felt–every tiny disappointment, every simple pleasure–was magnified by a thousand." They were within sight of the base now and the Doctor quickened his pace. "Now, if all your emotions are magnified by a thousand, imagine what it must feel like to be more keenly alone than anyone has ever felt."

Rose gasped. "You'd die."

"Exactly. A sympath needs to disperse its emotions, give them to others or else the frustration of a broken nail could kill it." The Doctor pointed the sonic screwdriver at the makeshift gate closing off the hole the Yeti had made in the fence and marched right through it.

"But I felt like dying," said Rose. "When it looked at me, I wanted to die."

"That's how it feeds," said the Doctor grimly. "The Dondolarians were meant to live in a symbiotic relationship with the Kamal Rhu. They were an empathic race, feeding off emotions. They lived on twin planets in the western arm of the Qual Galaxy. Perfect arrangement, worked for billions of years. Until humans entered the picture." He looked pointedly at Jack.

"Hey," he said, "that wasn't my fault, it was before my time."

The Doctor ignored him. "The Kamal Rhu lived on a planet rich in minerals. Very lucrative site for expansion mining. They were all wiped out in a matter of decades. And the Dondolarians had no one to feed off."

Rose's eyes widened. "So they came here?"

"They scattered, in time and space, looking for victims. They changed, became emotion-mad monsters. Non-empathic species weren't equipped to take the emotional overload; the Dondolarians became killers. And gradually, they all died, hunted down for what they'd done. Except, apparently for one." The Doctor paused. "That creature is the loneliest being in the universe. Imagine what it would be like. All you need is someone else to share the pain with, and fate brings you to the loneliest spot in the world." He swallowed hard.

"It got you, didn't it?" asked Rose gently.

The Doctor shook his head. "It didn't. Because I know how it feels."

**

Aaron and Cheryl didn't seem to have expected the three of them to come back at all.

"Wh-what are you doing?" stammered Cheryl as the Doctor burst through the front doors, Jack and Rose on either side. "I thought you'd been killed!"

"What's back there?" the Doctor asked, ignoring her questions. He was striding down the hallway with that look in his eyes that both frightened and excited Rose as she hurried to keep up. He was heading for those doors at the end of the hall, the ones they had been unable to open. "What are you keeping in there?"

He gave the doors a hard shove, but Cheryl blocked his way. "You're not authorized," she said importantly.

"Cheryl." The Doctor looked at her seriously. "Cheryl. Don't you want to know what killed your friends? Don't you want to know what's been killing all those people?"

Cheryl hesitated, but Aaron stepped in front of her. "I do," he said, pulling a ring of keys out of his pocket. "Here."

Cheryl turned on him. "What are you doing? Aaron, you'll be sacked!"

"I don't care," he said, his voice shaking. He marched up to the doors and unlocked them. "I want to know what killed them." He looked at the Doctor. "Can you find that out?"

"Oh, Aaron Lucas. I can and I will." He pushed the doors open. "Come on." He bounded through, Jack and Rose at his heels. After a moment's hesitation, Aaron glanced at Cheryl and followed them. When the doors closed, they were plunged into darkness.

"Lights," murmured the Doctor, "I need lights." Rose heard the sound of the sonic screwdriver and the lights flickered on. They were in an enormous warehouse-like room, packed floor-to-ceiling with boxes. However, the Doctor made a beeline for the large object in the center of the room. It was covered with a white sheet, which he yanked off, revealing a silver pod. It was about eight feet in diameter and lacked any visible entrance.

"Aha!" He took several steps back and looked at Aaron. "You found its ship. No wonder it's attacking you."

"That's been there forever," said Aaron. "They brought it in before I worked here. Patrick must have done it, or maybe even the team that was here before us."

"I've never seen a ship like that," remarked Jack.

The Doctor slipped his glasses on and leaned in closer. "Yeah, I'm not surprised. This isn't something you run across every day. It's similar to the TARDIS in a way." He pulled the sonic screwdriver out of his pocket and pointed it at the ship. He frowned. "Can't get it open. It'll need to do that itself."

"So what are we going to do?" asked Rose.

The Doctor took his glasses off. "We are going to give our Dondolarian friend his ship back."

"How?" asked Jack. "Can't exactly move it, can we?"

"No," said the Doctor thoughtfully. He straightened up. "We can't. But the TARDIS can. Aaron! Can you get those doors to the outside open?" Aaron sprang into action.

"Brilliant!" cried the Doctor. "Right. I'm going for the TARDIS. You lot get back inside."

"No way," said Rose. "We're not leaving you alone with that thing."

"Trust me, I'll be fine." He darted out the door.

Rose and Jack exchanged glances. Jack grinned. "I love it when he plays hard to get," he said, and they ran after him, Aaron on their heels.

The Doctor frowned as they caught up to him. "I thought I told you to stay inside."

"You did," said Jack. "We chose not to listen."

"That thing tried to kill us," said Rose. "We're not letting it do the same to you."

"Well, be careful," said the Doctor. "Dondolarians are smarter than they look. I ran into some years ago, back when… back before the Time War."

"What happened to them?" asked Jack.

The Doctor rubbed his face. "They died," he said finally. "My… my friend, he killed them. They were killing people. He didn't have a choice. So he killed them." The Doctor stuck his hands in his pockets. "I'm not going to let that happen this time."

The four of them walked in silence for a long time.

"Cheryl's going to kill me," said Aaron finally. "When I get back. Going to be sacked anyway, so it doesn't matter."

"You could come with us," said Rose conversationally. "We go all sorts of places. You'd love it out there."

The Doctor raised an eyebrow. "Rose, do you remember what happened the last time I let you keep one of your strays?"

"Are you talking about me?" asked Jack.

"Stop," said the Doctor suddenly. "It's close."

He had the thing he'd used to track Jack down out and was holding it in front of him. "Just around this corner." He reached over to Rose and pulled the sunglasses back down over her eyes. "Concentrate on not looking at it," he told Jack and Aaron.

"Why?" asked Aaron. "What's it do?"

"It's a telepath," said Jack. "It's got hypnotic ability. If you get a glimpse of it, it'll force you to make eye contact. That's when it overloads you with emotions until..." Jack trailed off, his gaze not meeting Rose's.

Aaron paled. "So Patrick… and Annie, they…"

"It made them feel so bad that they couldn't... just couldn't live anymore," said Rose softly. She remembered what it had made her see, the illusion of rejection she'd experienced as she'd watched the Doctor and Jack choose each other over her. Aaron looked frightened, but he did not turn back.

Suddenly, they turned the right corner and saw it. The Yeti was crouching in front of the TARDIS, blocking their way to it.

"What's that?" asked Aaron. "A phone box?"

"Don't look," the Doctor reminded him. Aaron turned away. The Doctor stepped forward calmly, his hands in his pockets. Rose could see Jack's face contorting; she reached out and tangled her fingers with his.

The Yeti stood up when it saw the Doctor. "Oh, no," said the Doctor quietly. "Your trick's not going to work on me." The Yeti paused, confused. "Yes, that's right. Your wavelengths are all wrong for me." He waved his hands around his head. "You're after humans and I'm not one."

"What?" said Aaron. "You're not human?" The Doctor, Rose and Jack ignored him. The Yeti let out a terrifying roar. Dark clouds began to gather above their heads.

"Oho!" crowed the Doctor. "You're a weather manipulator! I'd never heard that. Well. That explains everything, really. The TARDIS wasn't malfunctioning. I owe someone an apology." He glanced over his shoulder. "Sorry, Jack. I assumed it was something you did."

"No problem," said Jack weakly. Rose tightened her grip on his hand.

"Now, listen," said the Doctor to the Yeti. "This planet isn't yours to feed from! You have to listen to me, I can help!" His words were being lost in the howling wind. Snow began to fall around them. "I know where your ship is. People have taken it but you can't blame an entire species for the actions of a few. I can help!"

The Yeti charged. Rose screamed and Jack shoved her to the side. The Yeti grabbed the Doctor with both hands and lifted him.

"I understand your pain!" the Doctor screamed over the twin howls of the storm and the creature. "I know what it's like to be the last of your kind."

The Yeti hesitated.

"Yes, that's right," said the Doctor. Jack pulled Rose to her feet, but he kept her pressed against himself.

"You're feeling okay?" she whispered to him.

"Yeah," he replied. "I'm not getting any more emotional feedback."

"Yes," the Doctor was saying. "I get it. I can help. I understand. Come on." The Yeti gently set him back on the ground. "Yes, that's right. I know what it's like. I'm alone, too. I'm a Time Lord."

The Yeti let out a tremendous roar.

"Stop it!" screamed the Doctor. "We meant you no harm!"

Rose was hit by a powerful wave of despair.

The Time Lords were a threat, they killed without mercy. They were ruthless and cruel, power-mad, insane, murderers of a helpless, gentle race.

She stumbled, falling against Jack as they struggled to keep each other upright as they were inundated with the waves of feelings.

She saw fire and water and blood, bright light and falling, two lines snaking away from her in the darkness. There was no way out, no reason to continue.

Rose and Jack stumbled toward the edge. She was half-conscious of the stones her feet knocked loose and how far they fell, but all she could see was the pain. She pulled free of Jack's grip and she fell.

Suddenly, someone grabbed her wrists. It was Jack.

"Hang on, Rose," he said. "I've got you."

She blinked, trying to remember what had happened. She could feel that there was nothing below her feet. Slowly, she turned her head. The ground was thousands of feet away; all she could see below her were jagged rocks and sheer ice. Rose screamed.

"Calm down!" said Jack urgently. He was holding on to her wrists. "Come on." Aaron's face appeared beside Jack's and together they pulled Rose to safety.

"What happened?" she asked, collapsing against Jack in relief.

"The connection broke," he said, pulling her into his arms. "Look."

Rose squinted through the driving snow. The Yeti may have been forced to break its psychic connection with them, but it still had control of the weather. It was advancing on the Doctor, who was standing calmly before it, his expression grim.

"I gave you a chance," he said, his voice low and dangerous. "I gave you a choice." He was slowly backing away as the Yeti advanced. "I understand you've been hurt, your people have been hurt. The Time Lords are gone now. The one who hurt you is gone now. You've nothing to fear."

The Yeti lunged and the Doctor twisted away from its claws at the last second. "You can't see anything but your rage," he said sadly. Slowly, he backed away from the Yeti. "I know how you feel. You've lost every other member of your species, every other being that could even begin to understand what it means to be you." The Yeti advanced on him and he continued backing away. "Your grief has turned you into a monster!" cried the Doctor. "Can't you fight it?"

With one last tremendous roar, the Yeti threw itself at the Doctor. Rose screamed. At the last second, the Doctor whipped out the sonic screwdriver and pointed it in the air. Rose couldn't hear the sound it made, but the Yeti was clearly distressed. It staggered this way and that, as the Doctor looked on grimly. Finally, it stumbled to the edge and plummeted into the void.

Rose realized she'd been holding her breath and let it out with a gasp.

"What did he do?" she whispered.

"What he had to," said Jack evenly.

"He let it fall," said Aaron softly. "He said he'd help it and he just let it fall."

"It's what he had to do," repeated Jack edgily.

The Doctor walked slowly to the cliff and looked over it. "You were just like me," he said faintly. "A monster driven mad by loneliness. You were just like me." He turned away and headed back to where Rose, Jack and Aaron were standing.

"Oh, hello!" said the Doctor cheerfully, as Rose and Jack ran to hug him.

"Is it really gone?" asked Aaron, from his position, a few feet away.

"Yes," said the Doctor evenly. "It's really gone. It won't hurt anyone anymore." He swallowed. "None of them will."

Aaron nodded. "Right. Well. We should get back." He jerked his head in the direction in which they'd come. "Cheryl," he said by way of explanation. "She'll be worried. Of course, she'll say she wasn't, but I know she's worried."

The Doctor nodded. "Take care, then, Aaron Lucas."

He paused. "You're not coming?"

"This is where we bow out, I'm afraid. Our transport's right over there." He nodded to the TARDIS.

Aaron's mouth dropped open. "You really aren't human! I mean, that's… that's just a phone box."

"It's a spaceship," said Rose, grinning. "And it's bigger on the inside."

"But how?" Aaron asked, as he followed them over to the TARDIS and watched as they stepped inside. "How can it be… blimey, it really is!"

"It would be hard to explain," said the Doctor. "Just watch." He shut the door and went over to the console, pushing the right sequence of buttons to make the TARDIS dematerialize.

Rose leaned against the console and sighed. "Are you okay?" she asked the Doctor.

"Hrm?" He looked up. "Yeah. I'm fine."

"You did what you had to do," said Jack, coming up beside him and putting a hand on the Doctor's shoulder.

"Yeah."

Rose joined them, slipping an arm around the Doctor's waist. "You're not like that, you know," she told him, resting her head on his shoulder. "You're not like that at all. You're not a monster."

The Doctor sighed. "To it, I was. I'm a Time Lord. Time Lords hurt its family. You haven't met very many Time Lords."

She leaned up to kiss his cheek. "Yeah, but the one I have met is pretty brilliant."

The Doctor raised an eyebrow. "You think so?"

"Oh, yeah," said Jack, his arm going around the Doctor's waist. "Sexy, too."

"Well." The Doctor considered this. "You know, now that I think about it, you humans aren't so bad yourselves." He kissed her, in that way that made her knees go weak, especially when he kissed Jack next.

They stood that way for a while, with their arms around each other as the TARDIS spun through the Vortex. Finally, Rose broke the silence. "So where are we going next?" she asked, cocking her head.

The Doctor leaned over to turn some knobs and then looked back at his companions. "How does 1979 sound?"