Sorry for the delays in updating. Working through a few plot issues. Thank you all so much for your reviews!

Impact plus 17 hours 30 minutes

Airman Cora Ludwick lay curled on her side, wrapped in a scratchy military-issue blanket. She could feel the cold on her face, on her feet, and tried to curl more tightly into herself, conserving body heat. She was exhausted and wanted desperately to sleep, but didn't dare.

How had it all gone so wrong? It should have been so simple, so easy. One hand reached towards the radio that she still wore, touched it, but then she took her hand away. She wouldn't make the call, wouldn't ask for help. She would do this on her own, fix her own mistakes, prove that she could be trusted.

The sound of voices made her roll over, shivering as the blanket slipped down from her shoulders. Shadowy figures moved outside the privacy curtains surrounding the sickbay area; a slim hand drew back the curtain to admit Ling, a couple of guards and Dr. McKay. They went to Elizabeth's bed and knelt down beside her.

Cora pushed the blanket aside and rose to her knees. As quietly as possible, she slid her arms into the sleeves of her coat -- the one Dr. McKay had given her. A deeper shudder ran through her.

She had never been so terrified in her life -- terrified of discovery, of failure, of having to go through with the murders she knew she would have to commit to cover up her handiwork. She hated Dr. Weir, the woman who was trying to commit genocide against an entire race of alien beings who had only come to enlighten them all. Dr. Weir deserved to die, and so did Dr. McKay, who had been instrumental in implementing Weir's vile plans. But ... it was one thing to hate someone and believe that they deserved to die. It was another thing entirely to be the hand who carried out that death sentence.

Shoving her ice-cold hands deep into the pockets of her coat, Cora crept closer, watching as McKay knelt down beside Weir's still body. Her chest rose and fell rhythmically as one of the medics, Stepovich, forced air into the woman's still lungs.

"Stepovich, take a break," Ling told the young man, and her hand slid smoothly over his, taking over squeezing the ventilator.

"That seems so primitive. It ...really works?" McKay asked in a low voice. Cora crept a little closer, letting the shadows blur her outlines. She wasn't hidden; they could have looked up and seen her. But, then, it was the infirmary and she had every right to be there.

Ling's back was to Cora, but she could see McKay's face clearly. In the harsh light of the lanterns he looked a dozen years older than when she'd first encountered him in the engine room.

"It's all we have," Ling said simply. "She's not the only one we're keeping alive this way. It's tiring, though -- straining my staff even more than they already are."

McKay looked down at Elizabeth's unmoving form, then up at Ling with shadowed eyes. "Could I take a turn?"

Ling's hand did not pause on the ventilator, but Cora saw her shoulders tense slightly, then relax. "It's very tiring, and once you start, you can't stop, not without finding someone to take over for you. Not to stretch your arms, not to scratch your nose, not for anything. You understand that?"

"I understand," he said quietly.

Ling hesitated, then reached out with her free hand and gripped one of his hands, guided it to the rubber ball at the top of the mask. "It's easiest to pace it to your own breaths," she said. "And don't try to talk once you start. I know I'm talking, but I'm also counting in the back of my head. And I've been doing this for a while. Not only Dr. Weir's life, but also her brain, are at stake here if you don't keep her blood chemistry stable."

She slid his hand forward, and then, in a quick motion, slipped hers out from under it. There was the briefest pause as McKay's brain seemed to catch up with what was happening, and then he squeezed the bulb a bit convulsively, stopped, squeezed again.

"Slower. Easy. Time it to your breaths, and take slow breaths. Hyperventilating her is almost as bad as not giving her enough oxygen." Her hand settled over his, guided him through a few slow even squeezes, then let go. She nodded, and said, "Good. Keep it up," and stood up.

"Hey! Wait!" Panic overtook McKay's face, but except for the briefest hesitation, he didn't stop squeezing. "You can't leave me here! I'm not -- This is --"

"You're doing fine. I'm going to check on some of my other patients. I'll be within earshot at all times." She was standing with her head turned, and Cora could see her in profile -- could see the way that she was challenging Dr. McKay with her gaze. Cora had no idea what was going on between them, but she thought this seemed like a test of some kind. To what purpose, she could not imagine.

McKay looked down at Elizabeth again, and at his own hand steadily squeezing the mask, forcing vital oxygen into her lungs. He just nodded. Ling nodded too, and stepped away.

She didn't look in Cora's direction, and Cora just leaned on a crate, half-hidden, until Ling was busy checking the vitals of one of the other patients. Then she stole quietly towards McKay and Weir.

There they were -- the two people who could unmask her, the two people she had to kill. And Weir's life hung by such a fragile thread; it would be easy. McKay might be harder. But ... her frustration deepened as she realized that they were not isolated enough. There were too many witnesses around, no way to cover up her own tracks. There were a number of ways that she could kill Elizabeth while the woman's health was so fragile, but she'd have to get McKay alone somewhere.

Cora Ludwick had wanted to be a nurse all her life. It wasn't until becoming an Air Force medic and having actual experience in the field that she'd come to realize an unpleasant truth: she didn't like sick people. She didn't feel sympathy for them, but instead, a kind of horrified, pitying disgust. Seeing other people screaming in pain, vomiting, clutching at their own spilling intestines made her too dreadfully aware of her own fragility. And she could not help judging them, and finding them wanting -- she couldn't helping thinking that strong people, admirable people, would not scream and whimper and cry, wouldn't clutch their loved ones' bodies while breaking down in tears. Cora admired strength, scorned weakness ... and all she saw around her, every day, was weakness.

Being a perfectionist, she had continued to carry out her duties to the best of her ability, even though she did not want to soothe her patients' pain so much as she wanted to hit them and tell them to stop whining. She carried her true feelings inside her, a hidden, shameful secret ... until coming to Atlantis, and meeting Dr. Price. Until the late-night conversations in the Atlantis commissary when she had realized that there was a reason why she felt this way. She had come to perceive human beings as weak and flawed and ugly because they were. The Wraith were glory and strength, and she could overcome her feelings of inadequacy by working to stop the human persecution of the beautiful Wraith.

Now two humans stood in her way.

She would not allow them to stand between her and the Heaven on Earth she had been promised.

"Dr. McKay?" She pitched her voice low and soothing, but still he jumped. Cora put a sympathetic smile on her face. "You look tired. I can take over for you, for a little while, if you'd like to get some rest." At the moment, killing Elizabeth would be as easy as not squeezing a little rubber bulb for a few minutes. If she was very careful, she might even be able to gauge it so that she induced severe brain damage without actually, physically killing Elizabeth. And that would be perfect -- not just because it would make her handiwork completely undetectable, but also because the idea made her feel a little better about herself, a little less like some kind of killer nurse murdering patients. It wouldn't be murder if she didn't really kill Elizabeth, would it?

But Rodney just shook his head. "No. I've just started. I want to do this." He spoke in short sentences, pacing it so that he didn't lose track of squeezing the bulb. He really was serious about this.

And Cora hated him for it. "All right," she said, still using the skills of a lifetime to keep that sympathetic smile pasted on her face.

She moved away quickly before Dr. Ling could notice that she was up and about. She was still kicking herself for her mistake with the morphine. She had tried to calculate her overdose so that it would look like an accidental mistake, which meant that she couldn't give Elizabeth too much -- but apparently she hadn't given her enough. And then, worst of all, Dr. Ling had noticed when she'd tried to give her more. She still squirmed inside when she thought of it. Not only would they be watching her now, but ... she had to admit it to herself ... she really liked and respected Carol Ling, and didn't like the idea that the woman probably thought of her as incompetent now. Better incompetent than a killer, but still ... despite her dislike of her job, Cora had always tried to do it well, and she hated that she'd been brought down to the level of failure -- even in the name of a greater cause.

But there was no time for that. As far as anyone else was concerned, she was safely asleep in the sickbay. And when Dr. McKay got tired of playing nursemaid to a comatose Elizabeth, Cora would be ready for him.

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Impact plus 18 hours 5 minutes

They'd pushed the jumpers to the utmost, and shaved precious minutes from Simpson's ballpark estimates. The twenty hours had been cut down to something more like eighteen. But this still meant they were about three hours away from the planet.

They'd all given up on trying to sleep, even Ronon. Sheppard was back in the pilot's seat, with Simpson in the copilot position, trying to narrow down the location of the Daedalus on the ice world.

"These storms are wreaking havoc with the instruments," she complained. "It's making it very difficult to get a tight position lock on the Daedalus. Let alone making it impossible to reach them by radio."

"You think that's why we can't get through?" Sheppard asked. "Interference from the storm?"

She shook her head. "We're still much too far out. Assuming that they don't have power to boost their communications, they won't be able to read us until we're nearly in orbit. But from what I'm seeing, if they're under one of these storms then communications on the planet's surface are going to be a wreck. There's quite a lot of electrical activity ... we probably won't be able to contact Atlantis once we go down into the atmosphere."

"How big a storm are we talking here, Doc? Can we land in it?"

"Well, obviously we can," she said impatiently. "Whether or not it's a good idea ... that's a different story."

"Let's hope they're not under one of those storms, then."

"Yeah," she said, not sounding very hopeful. "Let's hope."

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TBC