There was a whistling sound, and the air around the Dalek shimmered briefly. The head of the thing pivoted slowly, pointing the blue lighted stick toward the corridor from which it had come. There was another whistle and another shimmering around it.

"We have to move now while it's distracted!" the Doctor hissed, suddenly close to Elsa's ear.

The Dalek pivoted its whole body toward the branching corridor, from which more whistles were coming. Elsa thought she also heard the heavy steps of the Ice Warriors.

"EXTERMINATE!" the Dalek shrieked.

A beam of light shot from one of its sticks, accompanied by a whining sound. There was a moan from the branching corridor, and the sound of a body hitting the floor. Elsa felt the Doctor pulling her close to the opposite wall and quickly moving around the Dalek. As she passed it at an uncomfortably close distance, she could see a small group of Ice Warriors in the corridor it was facing. Their sonic weapons were whistling furiously, but with no more effect than causing the air to shimmer around the metal thing. The Dalek was firing its beam of white light methodically at each of them in turn, shouting "EXTERMINATE!" each time. Its beam never missed, and every Martian it struck collapsed with a moaning of agony.

"Run!" the Doctor shouted.

There was a bend in the corridor ten feet away. Another shout of "EXTERMINATE" echoed behind Elsa as they were rounding it, accompanied by the whining of the Dalek beam. She tensed as she ran, but there was only the sound of an explosion some distance behind. It could have been the beam hitting a wall, but Elsa was not about to turn around to check. The Doctor had not let go of her hand, and she needed all her attention to keep up with him.

"How did the Dalek move so fast?" Anna panted.

"Probably another one, got into position before the lockdown began," the Doctor shouted back. "There should be another level of doors ahead."

He was proven right after they rounded the next bend in the corridor, and could see large panels slowly closing at the far end. The opening was still large enough when they reached it for all of them to pass through. Elsa noted as she did so that the panels were more than three feet thick.

"Wait!" Anna said as she crossed the threshold. "Where's Olaf?"

Elsa risked a glance behind her, and gasped. The Dalek had just rounded the last bend and was swiftly gliding toward them, although it was doubtful it would reach this door before it closed. But between them and the metal thing, there was Olaf, sauntering at what was a quick pace for him, but clearly not enough to reach them in time either.

"Olaf!" Anna shouted, jumping back through the closing door.

"Anna!" Elsa and Kristoff shouted in unison, while the Doctor roared "Don't be stupid, Freckles!"

Elsa did not hesitate and, slipping away from the Doctor's grasp, rushed into the shrinking space behind her sister. She had to sidle between the thick panels, and she was half crawling when she finally reached the other side.

"Anna! Come back!" she heard Kristoff shout, a second before the large door closed behind her with a definite clang.

"EXTERMINATE!" the Dalek shrieked, the bumps on either side of its head lighting as it spoke

A white beam of light lanced out of its stick, squarely hitting Olaf. The little snowman jumped, appearing black in the strange light, and fell on the floor face first.

"Olaf!" Anna yelled, as she ran toward their friend.

"Heh, look at that, I've been exterminated," Olaf said, raising his head. "I had never been exterminated before."

The Dalek stopped. A machine with no real features was not supposed to have any kind of expression to read, but Elsa got the strange feeling it was thinking. She rushed behind her sister toward Olaf.

"INCINERATE!" the Dalek shrieked.

Elsa, or rather her powers, were faster. A shot of snow hit the snowman, scattering him in all directions, a fraction of a second before another beam of light hit the ground where he had been, vaporising Elsa's snow in an instant. She saw the metal stick that was shooting the white beams twitch and slowly move to point at her. She ducked while a thick ice wall rose from the ground in front of her.

The wall cracked and exploded in a cloud of steam, shards of ice raining around her. Elsa backed off, noting out of the corner of her eye Anna gathering Olaf's body parts. With a mere thought she erected an ice wall between the Dalek and the three of them, concentrating on making it as thick as possible.

There was another shriek of "INCINERATE!" from behind the wall, which crumbled into steam as easily as the previous one.

"Run, Anna!" Elsa shouted to her sister. "Run with Olaf! I'll hold it off!"

"Where to, Elsa? The door is closed!" Anna said, running to her side with Olaf behind her.

Elsa concentrated. Ice rose from the floor under the Dalek, engulfing it into a bundle of ice spikes. She focused on quickly covering with ice the weapon arm of the metal thing.

For a second, there was no noise apart from the creaking of ice as it engulfed the Dalek, and the distant clatter of the remains of Elsa's previous ice wall belatedly hitting the ground. Then the whole structure vibrated and exploded outward, and the Dalek emerged from it, another of its beams of light hitting the floor uncomfortably close to Elsa.

Elsa willed the ice to disappear. There were too many shards flying around, and one of them could hit Anna, even while falling in this strange slow motion like everything on this planet. She erected a quick ice wall in front of her as she desperately backed away, but the barrier crumbled a second later, revealing the Dalek coming even closer.

Elsa clenched her teeth. She spared a glance in the direction of Anna, who had run back to the door and was hammering on the panels with her fists. The image of Anna illuminated in black and white briefly crossed her mind, and this mere thought scared her to the point of making her legs wobble. It had been hard enough to see it happen to Olaf, even though the little snowman had been miraculously unharmed.

A spray of ice flew from her fingers, hitting the Dalek. To Elsa's horror, the ice rebounded as if it had hit a wall. She only had the time to jump aside behind a rising ice wall as the thing shot another beam of light. She threw two other missiles of ice at it, and erected another ice wall while stumbling backward. She had the time to see her ice shards bounce harmlessly off the thing before the ice hid it from view for a second.

Elsa felt herself filled with unspeakable terror. She had wilfully aimed at the thing with her ice, the same ice that had struck Anna twice before, and nothing had happened to it. She would never have dreamt to use this as an attack - at least, in half of her memories, but if the Doctor was right she could choose to ignore the other half - and now that she had done it out of desperation, it had failed.

Elsa backed up, raising walls after walls of ice, which invariably exploded as the Dalek went through them as if they were made of paper. The thing kept advancing relentlessly, and Elsa knew she would soon find herself backed against the large door. She did not dare turn to look at Anna, but she could hear her sister, now very close, grunting with effort, probably in a futile attempt to force the door open. Elsa knew Anna was stronger than she looked, but she also knew for a fact that her sister had never been able to open the castle gates by herself – she had tried once, on a bet - and this door seemed made of incredibly sturdier stuff, not to mention a lot thicker.

Elsa felt an unfamiliar emotion rise inside her, slowly overcoming the abject fear she felt. This unstoppable, ugly thing kept advancing, ignoring all her efforts to stop or even delay it. It had shrugged off an attack that had nearly killed her sister as if it had been nothing more than a pebble against a wall. It did not want to speak, apart from shouting that it wanted to kill them. It even looked like a dark, twisted parody of a snowman, a word that evoked cherished memories to her and Anna. It had remorselessly killed the unsettling but otherwise decent Ice Warriors. It had turned an extraordinary adventure in a new world into a nightmare. It had shot Olaf. It threatened Anna.

Elsa's face contorted into a rictus as a burning hatred filled her, slowly pushing away the fear. She hated this relentless, ugly, metal killer that was advancing on her and trying to kill her family. She hated its bronze colour. She hated its shape, its shrieking voice, the beam of light that kept sprouting from its arm. She hated it as she had never hated anything else before. Even the muddled memories she got from the alterations to her past did not contain an emotion as intense as this. Even Hans did not evoke such burning hatred – at least he had had the common sense of going down after one punch from Anna. The passing thought of Anna hurting her delicate hands on this wretched thing reinforced the flow of hatred now coursing through her.

Ice. Ice was water. And water was everywhere. Elsa's powers allowed her to seize this water, even where there was so little of it, and make ice or snow out of it. Quantity was not the issue – a drop of water could become as much snow or ice as she wanted.

There was water in the thing. There always was. Elsa could feel it. She reached out with her powers, trying to connect with this water deep inside the metal thing. One drop would be enough.

Her last ice wall exploded. The Dalek emerged, now less than twenty feet from her, still advancing, still shrieking. She did not bother to create another wall. She was calling the water inside the thing, willing it into ice, pouring the entire strength of her powers in a way she had never done before, for something she had never even wanted to consider doing.

And the ice, hidden inside the water, answered, and obeyed, and grew.

Elsa felt her heart accelerate, as if she was running at the top of her strength instead of awkwardly stumbling backwards. For the first time in her life she actually felt the strain on her powers, as if they were another muscle that she was overexerting. Her vision became blurry, but she was not using it any more. All her senses were now relegated to the background, behind what she could feel from her powers, the terrible pull she was exerting on the water to become ice, and turn everything around it into ice as well.

She was vaguely aware of the Dalek stopping less than ten feet from her. It shrieked something, but Elsa ignored that too. She felt ice expanding, engulfing everything in its path. It was what had happened to Anna, when Elsa had planted this ice shard in her heart. But now Elsa was willing the process to occur, calling the ice onto the thing. And it was doubtful it would be able to perform an act of true love to save itself. Did it even have a heart?

Elsa tasted blood. Her legs buckled under her, and she slowly sank on her knees. She could feel the thing pulling back, trying to resist the advance of the ice. But the ice was there, and it would not go away if Elsa did not want it. And now she was putting every fibre of strength in her body to push the ice forward, to make it expand further and further.

Elsa extended a hand toward the thing, invoking more and more ice. She had to steady herself with her other hand on the floor. She was not even looking at the Dalek any more. It seemed to have wobbled, and shrieked something that was abruptly cut. At least it was not firing any more.

Her head buzzed. She relentlessly pulled the ice forward, forcing it to keep expanding, and converting, and advancing. She was dimly aware of some shouting behind her, maybe even of a hand on her shoulder, but she ignored it. There was still some matter inside the thing, something that resisted the pull of ice. She did not know how that was possible, but the thing had been fighting back. She had even felt ice receding once or twice when she had not concentrated enough. She could not stop now, not at the risk of seeing all her efforts reduced to nothing.

She sniffed, feeling her nostrils itching. The ice was advancing, and now, like a see-saw finally tipping, it began spreading faster the more of it there was. But she kept encouraging it to spread, and spread again, and expand, further and further…

And then the ice ran out of Dalek.

Elsa blinked muzzily, noticing a small red dot on the floor below her. As she looked, she saw another red dot appear, and another. She sniffed again. Her nose definitely seemed to be running. It was not the time to catch another cold.

She became vaguely aware of her sister's voice, talking to her. She managed to raise her head to look into Anna's eyes. For some reason, Anna seemed distraught, but Elsa could not focus enough to try understanding why. She felt drained. She absent-mindedly wiped her nose, and looked with puzzlement at the red smear on her hand.

A thought struck her, and she turned to look at the advancing Dalek. She managed to focus on it, or rather, on the object that was now standing in its place.

In front of her was an ice statue of a Dalek.

Elsa turned to her sister and smiled groggily.

"You're safe…" was all she managed to utter before drifting into unconsciousness.


"Elsa? Elsa?" Anna called, shaking her sister's limp body. She glanced uncomfortably at the statue in front of her and tried to see whether something else was approaching from behind it.

"Isn't it a bad time to be taking a nap?" Olaf asked.

There was a clanging sound behind her. Anna turned to see the thick door slowly grinding open, accompanied by the whistling of the sonic screwdriver. The Doctor's stern face appeared through the widening gap, with Kristoff's hovering worryingly right behind him.

"Doctor, she has fainted!" she called.

"If she was hit by the Dalek's weapon, she's not fainting, Freckles, I'm sorry to tell you that."

With another grinding noise the door stopped, leaving only a small space between the panels.

"She was not hit, Doctor!" Anna said. "She… she made something to the Dalek."

"You stay here, Reindeer Man," the Doctor said, grunting as he crawled between the two panels. "You are too thick to go through anyway, and I don't know how long these will stay open. Freckles, come quick."

He joined Anna, who managed to haul her unconscious sister to her feet. The Doctor glanced at the statue of the Dalek while she pulled Elsa toward the door. As Anna sidled through the gap, with some help from Kristoff and Olaf to manhandle Elsa's body through it, she heard the whistling of the sonic screwdriver, in a pitch she had not heard before, following by the sound of ice breaking apart and lots of icicles hitting the floor. She turned back to discover the Doctor sidling through the gap right behind her.

"Hurry up, Freckles. These could close at any moment, and they won't stop if you are in the way."

He crawled out of the gap behind her, gave a quick glance at the small group, then waved his whistling sonic screwdriver. With another metallic groan, the door snapped closed.

"Elsa?" Anna called, gently tapping the cheek of her sister, whom Kristoff had picked up in his arms. "Elsa, wake up! Doctor, can't you do something?"

"About what?"

"About Elsa! She fainted! And she got a nosebleed."

The Doctor waved his whistling sonic screwdriver over the unconscious Elsa for a few seconds, then examined the side of the wand.

"She's exhausted," he commented. "But fine otherwise. She should wake up in her own time."

"Can't we let her rest until she wakes up? Now that the Dalek is… not attacking us any more. Or do we still have to keep running before the next door closes?"

"If there were other doors, they would probably be closed by now," the Doctor said. "But this should have been the last one."

'So… can we stop here until Elsa wakes up? Kristoff will be tired too."

"No, that's OK, Anna," Kristoff said. "I can go on for some time like this. But she would need something more comfortable than my arms to rest."

"Oh your arms can be quite… forget it," Anna said, blushing. "Can we do that, Doctor? Or do we still have to run?"

"To be perfectly honest with you, I don't know," the Doctor said, slowly walking to a door on the side of the corridor. "But we can hope the Daleks will not be able to reach this part of the base for a little while, so we should have some time for your sister to recover. And I think I can do something with this console," he added as the door opened to the whistling of his sonic screwdriver, revealing a deserted room furnished with strange devices.

"Is Elsa going to be OK?" asked Olaf as they all entered the room.

"Oh, yes, certainly, Olaf," Anna said, smiling at the little snowman with a confidence she forced herself to feel as well. Something nagged at her mind as she looked at him, but she could not put her finger on it.

The room also contained a large slab of something that looked like stone or metal. Anna hovered around it as Kristoff gently deposited her still unconscious sister on it, while the Doctor waved his sonic screwdriver over the devices. Elsa's face was even paler than usual, and the specks of blood near her nostrils did nothing to improve it. Anna's only experiences with a nosebleed were when she had struck her nose, although she had heard that some illnesses could cause this.

"Why did she get a nosebleed?" Anna asked, delicately wiping the blood away.

"Probably for the same reason she fainted, exhaustion. You do realise that she managed to turn a Dalek into an ice statue? Not a lot of people can do that," the Doctor answered without looking up from his apparatuses.

"Oh, she did it to me once, by accident, and she was not even trying."

"You are not a Dalek, Freckles. I told you already, the Daleks have been engineered to be the ultimate survivor. They have protection against all kinds of attacks, and they may even have some against cryothaumaturgical ones. What your sister did is no easy feat."

"Er, what is cryotham… thaum…"

"Ice magic."

"Elsa? Can you hear me?" Anna asked, gently stroking her sister's cheek.

"Elsa? Are you all right?" Olaf asked from the other side of the slab, his head barely on its level.

"She's just sleeping," Anna said, smiling reassuringly at the little snowman, wishing that someone could be smiling reassuringly at her. Kristoff only looked worried and at the moment she did not find the Doctor to be the best person to turn to for reassurance. Something finally clicked in her mind as she looked at Olaf. "Olaf! Where is your flurry?"

Elsa stirred and moaned softly. Her eyes fluttered open.

"Elsa? Are you all right?" Anna asked excitedly. "We're safe! We're in a… a safer part of the Ice Warrior base! Are you all right?"

"You are either very lucky or very powerful, Platinum," the Doctor said dryly. "Not many people can say they fought a Dalek head-on and survived."

Elsa seemed to shiver. She looked at the people around her, and tried to sit up. Anna helped her gently.

"Are you all right?" she asked.

Elsa kept looking wildly around her.

"Elsa! We escaped the Dalek, the Doctor opened up the door to let us pass through," Anna said. "We are safe! Thanks to you!"

"Anna…" Elsa said weakly, turning to her sister. She breathed heavily, forming a cloud of vapour in the cold air.

"I'm here. You saved us, Elsa," Anna said, gently hugging her sister. Elsa was trembling.

"Anna…" Elsa said, her eyes widening with shock. "I'm… I'm cold!"