Author's Note: Hello, my lovelies! This is my first foray into Castle fanfic, but I just couldn't resist. This was prompted by my frustrations with the infamous Freezer Scene (mostly my personal belief that two intelligent people from New York would, collectively, know more than "absolutely nothing" regarding hypothermia, and my sorrow over all the wasted hardcore cuddling opportunities). I hope you enjoy.

Disclaimer: If I actually owned any of this nonsense, what you would have seen on the show would have resembled what you are about to read.

To be honest, Kate Beckett hadn't really thought that shooting the door would accomplish much. It just felt better than doing nothing. Anything would have felt better than just standing there, watching him watching her with that godawful, frightened look in his eyes. "Castle… I could use a silver lining right about now, okay?" Beckett said, not quite able to meet his eyes.

"Yeah. Um…" Castle stepped toward her, shoulders hunched in a mostly ineffectual attempt to keep his neck warm. "I wish I had one," he said. Looking up at him, taking in his worried expression, she offered a smile that she hoped would come across as brave.

Castle returned it briefly, and then his expression changed. She had seen his 'just got an idea' face often enough to recognize it immediately. "Hang on," he said, before turning away and walking over to Jamal's body beneath its plastic shroud. With a whispered apology to the corpse-which Beckett could hear clearly enough in the small space-Castle whisked off the plastic sheet and bundled it in his arms.

"I hope you're not planning on slicing him open like a tauntaun," Beckett said dryly, "because we wouldn't fit."

Castle looked back at her, astonished, and then grinned. "While I truly appreciate the Star Wars reference, Beckett, I think the plastic will do just as well."

"Do what just as well?" Beckett eyed the thin sheet dubiously.

"Insulate." He crossed back over to her, took in her expression, and continued, "Look, I'm no expert, but it can get cold in the Hamptons, so I made sure Alexis knew at least the basics of how to stave off hypothermia."

Beckett raised an eyebrow. "Are you sure it wasn't Alexis making sure you knew the basics?"

Castle's brief hesitation was all the answer she needed. "Don't make me blush, Detective; it's a waste of valuable body heat," he said, shaking out the plastic sheet. The rustle masked Beckett's involuntary snort of amusement. "And for your information," he continued, "I've researched hypothermia. Not extensively, but I thought it might make for an interesting plot point." Beckett bit back a smirk at Castle's wounded pride, but the mirth she was feeling was snuffed out moments later by the look he gave her. It was grave and determined, and so damn earnest it might have brought tears to her eyes if they weren't already misting up from the cold.

"If our only option is waiting to be rescued," he said quietly, "then I'd like us to be able to wait as long as possible."

Beckett nodded her agreement, not quite trusting her voice.

"Okay." Castle took a breath, as if steadying himself, and nodded at her. "Unzip your jacket."

Beckett stiffened and gave him a withering look. "That doesn't sound conducive to warming."

"I'm not asking you to take it off. Look, mine's open," he said, almost pleading. "You'll thank me in a minute."

"You sure about that?" she asked.

Castle swept the plastic around his shoulders like a cape and gave her a perturbed sideways glance. "No."

Beckett raised an eyebrow at him, but unzipped her jacket. She hated to admit it, even to herself, but Castle did probably know more about hypothermia than she did. The only bit of trivia she could remember involved nudity and a sleeping bag, and even if they'd had a sleeping bag, there was no way in hell Castle was getting that lucky.

He sat down, wincing as he came into contact with the frost-covered floor, and loosely crossed his legs. "Okay," he said, wincing again for reasons that Beckett suspected had nothing to do with the cold, "now, you just sit here..."

Beckett didn't move. Nor did she say anything, though several potential exclamations presented themselves, most of them variations on the theme: you have got to be shitting me. If Castle's expression was anything to go by, she might as well have spoken aloud.

"I'll behave myself," he promised. Though it probably took some effort on his part, he managed to school his expression into something very like reproach. "Our lives are at stake, Kate."

Now it was her turn to blush. He was right, and he was obviously no more comfortable with the idea than she was. Her hesitation seemed childish in retrospect. Gritting her teeth in annoyance, both at herself and at the entire situation, she gingerly lowered herself to the ground.

Castle busied himself with the plastic sheet, giving her time to adjust. She needed it; she wasn't on his lap so much as between his legs, and the floor was freezing. She'd probably be numb within minutes... which could be a blessing, she supposed.

"Could you lean forward a bit?" Castle asked, frowning over her shoulder at what must have been a misbehaving bit of plastic. Beckett swallowed a few sharp comments about how little space there was and leaned towards him, all but burying her face in his shoulder. The plastic rustled, and he made a small, triumphant sound. "There. You can lean back a little if you want."

Beckett lifted her head and took in Castle's handiwork. He'd curled the plastic sheet into a rough cone shape, like a teepee. It was open in the top, so they wouldn't smother, but the air was so still inside the cone that it already seemed a bit warmer. "Nice work," she said, impressed in spite of herself.

"Thanks. It should stay up without me holding it if I've rigged it right." He pulled his hands back, eyeing the cone with some trepidation, and visibly relaxed when it stayed put.

"It already feels better," Beckett said, though she was realizing that the effect was not that great. Better than well below freezing was still pretty damn cold, all things considered, and the plastic was thin enough that she doubted it would hold in much heat. She ducked her head, not wanting Castle to see her expression as she tried to rub some feeling back into her fingers.

"Here," Castle said, putting a hand on her shoulder, "scoot a bit closer." When she hesitated, he explained, "You can put your hands inside my coat. It'll be warmer."

Warmer sounded good, but she wouldn't be able to move much closer to him without wrapping her legs around him. Part of her was mortified by the thought, but the larger part of her didn't care what it took to stop shivering. Pressing her lips together, she rearranged herself, moving carefully to avoid upsetting their plastic tent.

"Um," Castle said, his eyebrows shooting up into his hairline.

Beckett glanced up at him. "I'm armed, Castle."

"Noted," he replied, looking up at the plastic with more intensity than was probably necessary.

Once she was as comfortable as she thought she was likely to get (i.e. not very), Beckett gingerly poked her hands between his shirt and his jacket. He hadn't been lying; it was warmer. Before she knew it, she was wrapping her arms around him, pulling herself closer, and tucking her head over his shoulder. It felt fantastic. She managed to stop herself from sighing, but only just.

Castle, for his part, seemed unable to move. She could see his arm hovering beside her, though she wasn't sure if it was fear or shock that held him back. Biting back a smile, she said, "I suppose you want to return the favor."

She heard him swallow. "Well... in the interest of not freezing to death..."

Now she did sigh, a little huff of exasperation. "Go ahead. This was your idea." Then she shivered, and if her words hadn't convinced him, that did. His arms closed around her, his hands tucked beneath the hem of her jacket. Now she understood why he'd wanted her jacket open-the exchange of body heat was easier with fewer layers. She almost felt snug. The arrangement had more than its fair share of awkward, but damn if it wasn't working well enough for her to start silently recalculating their estimated survival time. It was definitely higher than it had been ten minutes ago.

"I'm sorry," Castle said a few minutes later, startling her.

"What?" she considered pulling away so she could frown at him, but decided against re-exposing her front to the cold air. She settled for frowning at the plastic sheet a few inches from her nose. "Why?"

"For getting you into this. Going rogue."

For a moment, Beckett was speechless-not because she had nothing to say, but because she had plenty to say and didn't know where to begin. She was brimming with indignation, and it hadn't even taken ten words on his part to get her there. He certainly had a way with them. "This isn't your fault."

"It was my idea."

Beckett almost did pull away at that, outraged at hearing her own words thrown back at her-as if she'd meant them as an accusation! Did he honestly think that she was blaming him? "I didn't have to indulge it," she snapped. "It was my call, Castle. I should be the one apologizing." Belatedly, she realized that she hadn't sounded the least bit apologetic.

There was an uncomfortable pause.

"Good point," Castle said, trying to lighten the mood, no doubt. "In that case, I forgive you."

She should have been mollified, but she was still angry. Something hadn't been addressed-something important, though she couldn't figure out what. She mentally reviewed the conversation, and then it hit her. "And, Castle? Don't talk about 'getting me into this,' like I'm the only one here who matters. We're both in this." Perhaps it was nitpicky of her to complain, but even if he hadn't meant anything by it, a writer should choose his words more carefully, damn it.

For a few moments, Castle's only response was a slight tightening of his grip. "Okay," he said.

Another silence fell, this one more companionable than the last. Beckett blinked a few times, resisting the impulse to close her eyes. Falling asleep had to be a bad idea; she just couldn't think of anything else to do besides talk. She didn't know of any topics of conversation appropriate for sitting in a freezer and waiting for improbable rescue. Anything too light would be ludicrous, and she wasn't sure she wanted to go in the other direction.

As if reading her mind, Castle said, "We need to talk."

Beckett hesitated, fighting back the mild surge of panic the phrase had induced. "About what?"

"Anything, as long as it keeps us awake." He shifted. "Nothing too boring. I'm open to ideas."

Relaxing a little, Beckett tried to think of something suitably interesting. It was harder than she thought it would be. She wasn't about to bring up Josh again-she already felt bad for dumping her relationship woes on Castle when they were sitting in quarantine-but so much of the rest of her life was spent with Castle in tow, what else could she tell him that he didn't already know? They were beyond small talk. But if small talk was out, what did that leave?

"So," Castle said, breaking the silence, "how long were you planning on holding out on me?"

Beckett started. Had he been able to see her face, he probably would have laughed at the uncharacteristic deer-in-headlights expression she was undoubtedly wearing. "What?" she said, her voice higher than usual.

"I can't believe it took me this long to get a Star Wars reference out of you." He was smiling; she could hear it in his tone. Briefly, she debated the relative merits of leaving her arm where it was warmer versus pulling it out for the purpose of smacking him. "I didn't know you made Star Wars references," he continued, apparently oblivious to the discomfort he'd caused. "I didn't know you'd seen Star Wars!"

"Everyone has seen Star Wars." Beckett rolled her eyes.

"What, did you think I wouldn't appreciate it?" Castle asked in exaggerated indignation. "You know I have the lightsaber app on my phone."

Beckett smiled in spite of herself. She did know; he had whipped out his phone one day and had an epic mock battle with Esposito in the bullpen, ending with Esposito triumphant and Castle slumped to the floor beside her desk in a drawn-out parody of agonizing death. It had distracted her from some important paperwork, but she'd been laughing too hard to scold. "Too bad you don't have a real lightsaber. One of those would come in handy right about now."

"Very true," came the grave reply. Then, a faint note of concern in his voice, he asked, "How are you holding up?"

Her impulse was to say that she was fine, but given the circumstances, he would probably call bullshit. Still, I'm fucking freezing, not to mention embarrassed that I have to sit here and cling to you like a koala bear just to keep my extremities from dropping off, didn't seem like a viable response, either. "Better," she finally said. "I can just about feel my fingers again." There. Honest, but not too honest. Castle shivered, and Beckett frowned. "You?"

"Fine."

She almost laughed. "Bullshit."

"I've been better..."

"I'm right here,Castle. Do you think you can shiver without me noticing?"

"Shivering's good," he objected. "Well, comparatively good."

Beckett resisted the impulse to ask if crazy talk was a symptom of hypothermia, and instead asked, "Compared to what?"

Castle hesitated. "Being so cold that your body stops bothering?"

She no longer felt like laughing. "Castle... what exactly are we dealing with, here?" When he didn't reply, she gave his back a brief rub. It was as close as she could get to snapping her fingers in his face without resorting to pinching (which was still an option, especially if he didn't answer her question in the next ten seconds). "Come on," she prompted in a tone she usually reserved for the interrogation room, "I want to know what we're up against."

"Well," he began, "keep in mind that it's been a while since I looked it up. I don't remember everything, and I'm not positive that what I do remember is accurate."

"Fine. Just tell me what you remember."

Castle's sigh ruffled her hair. "Shivering is the first symptom. It means things aren't too bad, yet. Other symptoms include confusion, impaired motor skills, drowsiness... apathy..." he trailed off.

Beckett winced at 'apathy.' How long would they last if they stopped caring? Then again, a small part of her pointed out, it might be better that way, at the end. It might be nice to not mind so much. Not wanting to hear any more from that part of herself, Beckett gave Castle's back another little scrub. "Anything else?"

"Hm?" Castle started. "Sorry, I just got a bit tired and lost interest. What were we talking about?"

For a moment, Beckett was speechless. Then, she pinched him.

"Ow!" Castle yelped, though she could clearly hear an undercurrent of laughter beneath the indignation.

"Don't be an ass," Beckett snapped, her voice shaking with mingled annoyance and relief.

"I couldn't resist," he said, still amused. But when he added, "I'm sorry," it sounded sincere. Then, to Beckett's surprise, he punctuated his apology by rubbing a few slow, soothing circles against her back.

You started it, she realized once she'd gotten over the initial shock. She couldn't object without sounding hypocritical at best; nor, to be honest, was she certain that she wanted to object at all. It was... nice. Comforting-not that she would have admitted to wanting any comfort beyond a significant increase in the ambient temperature. As he continued, it suddenly occurred to her that he might not even realize what he was doing; it could just be an absent-minded, automatic gesture from a good father in Soothing Mode.

Or maybe he knew exactly what he was doing, and was waiting to see how she'd react. What the hell are you playing at, Castle?

Maybe he's not playing at anything. Her breath hitched, and she realized with no small amount of mortification that she was on the verge of tears. She turned her head away, pressing her cheek against the wooly roughness of his coat, and prayed he wouldn't notice.

But of course he noticed. His hand had stilled the moment her breath had caught. "Beckett?"

She wanted to respond, but she knew any attempt at speech would as likely result in a sob as anything coherent. She clamped her lips together in an attempt to stop them from trembling. Get ahold of yourself!

"Hey," Castle said, worry creeping into his tone. Of course he couldn't just drop it; heaven forbid she survive this ordeal with her dignity intact. "Are you okay?"

'I'm fine, Castle,'she wanted to say, even though she was far from it. She had avoided thinking about the worst case scenario because she figured that was the sensible thing to do; there was nothing to be gained from dwelling on how bad things could get. Now, as that no-longer-quite-so-small part of her occupied itself by alternately screaming, What if you die in here? and What if HE dies in here? she realized that the real reason she'd avoided thinking about the worst case scenario was because it terrified her.

Castle was still waiting for a response. All she managed was an unsteady exhalation that might as well have been a 'no.'

A beat later, Castle had removed his hands from beneath her jacket and placed them on her shoulders. Leaning back, he gently pushed her away until he could look down at her. Beckett ducked her head, though she knew she was only delaying the inevitable, and a moment later one of his hands was beneath her chin, tilting her face up. Castle took in her expression, and then looked stricken. "Kate..."

She ducked her head again, embarrassed and upset and guilty because now she'd upset him. He'd been feeling cheerful enough to make a joke, and she'd responded with a damn panic attack. She shivered. Castle hesitated, and then pulled her back toward him, wrapping his arms around her in a hug that probably had little to do with the economical exchange of body heat. That was just as well; she was pretty sure her shivering had little to do with the cold. Burying her face in the warm gap between his neck and his turned-up coat collar, she tried to steady her breathing.

"I'm sorry," Castle repeated, sounding almost frantic. "Kate, I... I'll never joke about hypothermia again."

She let out a huff of air that was somewhere between a laugh and a sob. She wasn't upset because he'd made a stupid joke, but she didn't think she could articulate just what had upset her. She wasn't certain that she even understood it, herself—not completely. Given the circumstances, she wasn't sure she wanted to.

"I won't even make sarcastic comments at the end of 'Titanic,' I promise."

A watery chuckle escaped her, and she felt the panic begin to subside. Castle was still talking as if it was a given that they would make it out, and the last thing she wanted to do was call that unspoken assumption into question. "Don't promise that," she replied, her voice unsteady but at least under control. "I'd hate to think I ruined 'Titanic' for you."

She could feel him relax a little, and heard his faint sigh of relief. "Are you sure?" he asked, substantially less frantic than he had been a few moments ago. "I take my promises very seriously."

The impulse to say, Promise we'll get out of here, struck her, but she bit it back. She knew he would, and she knew he couldn't keep it; their only chance of getting out was being found, and there were more important things to look for in the city than two people who, in all likelihood, weren't even technically missing. "Yeah, I'm sure."

"You could pinch me again, if it would make you feel better," he suggested. "I deserve it." Beckett smiled into his shirt collar as he tentatively resumed rubbing her back. "I was an ass," he admitted. "I'm sorry you're stuck with me."

"Stop apologizing," Beckett said, her tone sharper than she'd intended. Hugging him a bit tighter, she added in a gentler tone, "I'm glad you're here." They fell into a comfortable silence, and it wasn't until after a minute had passed that the implications of what she had said sunk in. "I mean, I'm not glad you're locked in a freezer…"

"I know what you meant," he reassured her—grinning, from the sound of it. He turned his head slightly, resting his cheek against her hair. "I'm glad I'm here, too."

So ends Part the First. Part the Second is still in production. If you'd like to hurry things along, leave a review! I get so nervy about characterization, a little encouragement goes a long way.