AN: Thanks so much for all the lovely reviews!! I really appreciate it. :D Just wanted to say two things: One, the next chapter (chapter 4) will be the last chapter, because I always meant for this to be a 4-parter. However, it will be loooong. Two, I'm not really happy with this chapter, so be kind! I just had to get it out so I can start on Part 4. Again, thank you!!

CHAPTER THREE

"I am getting seriously sick of doing this," said Chuck as he walked up the wide steps toward the Valentine mansion. He straightened his bowtie with one hand, feeling conspicuous and awkward in his tux.

"What, getting to wear incredibly fancy clothes and crash incredibly fancy parties?" Sarah teased as she slipped her hand into the crook of his elbow, smiling up at him. He managed a tight smile in return, something twisting in the pit of his belly. She looked gorgeous, as usual, in her floor length dark purple gown, which was high in front and practically nonexistent in the back. As he looked down at her smiling face, Chuck was torn between the ever-present desire to kiss her and the ever-present worry that he knew so little about her. He didn't even really know who she was.

"It'll be fine, Chuck. We just have to get access behind the scenes and do some more snooping." The look she shot him was almost playful. Chuck could see she was feeling good tonight, and it made him feel just a little bit worse for some reason. She actually enjoyed this lie sometimes, but it was wearing him down bit by bit.

"Right. Snooping for smallpox. Totally normal." She squeezed his arm as they walked through the doors. Chuck put on his self-confident Super Spy smile. "Charles Charmichael and Sarah Walker." The server checked the guest list, nodded, and welcomed them in to the house. Chuck swallowed and tried to act like he normally went to parties that cost millions, in mansions that cost even more.

Elegant couples swirled around the ballroom, flitting from group to group and table to table. There were flutes of champagne and delicate little plates of food on each table; the guests didn't touch the food but went straight for the champagne. Appearances, you know.

"So, how are we going to get out of this room?" Chuck asked. The ballroom was surrounded by huge glass windows, and one wide staircase on each of the four walls, each leading to the second floor. People mingled on the balcony, looking down at the expensively dressed people below.

"We're going to use the same tactic we used at Valentine's last part," replied Sarah, her voice all business. "It worked quite efficiently."

"The 'drunken couple making out and stumbling around the house' tactic?" Chuck's voice was more than a little panicked. He wiped suddenly sweaty palms on his pants. "I don't know if that's such a good idea."

Sarah looked up at him, her eyes innocently confused. "Why? It'll be perfectly fine, I promise. I gave you my word that I'd protect you," she said seriously, her eyes sweeping the room, presumably looking for security cameras and guards.

"That's not exactly what I'm worried about," Chuck muttered, but Sarah appeared not to hear him. Her hand tightened on his arm.

"There's the birthday boy," she whispered in a sing-song voice. Chuck looked down at her with mild astonishment. She was never this…happy was the wrong word because she was happy, though it was rare. She was never this playful.

Just then, music started up – there was a string quartet in one corner of the huge ballroom playing a Beethoven concerto. Sarah turned to face him, a smile on her lips.

"Want to dance?"

Chuck almost fell over. What was going on with this day? "Are you…feeling okay? This is a mission, remember?"

She shrugged in a way that made her see much younger than…however old she was. "I know. I just want to forget about smallpox and the end of the world for a few minutes." How could he begrudge her that? How could he begrudge her anything? Chuck swallowed and followed her onto the dance floor, where everyone who was dancing there looked like they had had professional training.

Then Sarah was in his arms, elegantly swaying them back and forth – Chuck let her lead, really – as elegantly as she could with Chuck's awkward, 6 foot plus frame. While he was trying not to step on her, he let himself notice how fluidly her body moved. It was very obvious that she loved to dance, and that she was good at it. Very good at it.

She rested her head lightly on his shoulder with a sigh. "I love dancing," he heard her say quietly, her voice wistful. He didn't say anything, thinking instead of the night they had first gone out, before he had known she was CIA, before he had known what was going on inside his head. He remembered the look in her eyes when they had been dancing, the way her body had moved, her free smile.

But it hadn't been a free smile. She had been on a mission then, he just hadn't known it. Something twisted in his gut. That was the trouble with being pretty much head over heels for a secret agent: you could never quite tell when something was an act or not.

The smell of Sarah's hair right below his nose felt real. The way her hand was entwined in his felt real, same with the way she was peacefully resting her head on his shoulder. But Chuck couldn't enjoy it. He didn't know this woman in his arms, and every time he felt himself dreaming about some bright, shiny future with her, the perfect image got seriously tarnished by that fact. Not that they ever would have that shiny future, as much as Chuck wanted it. The CIA was her life, and that meant he would never know who she was, or exactly what she was doing at any given time.

Someone tapped his shoulder. Turning his head, he felt Sarah straighten and saw Casey in a waiter's uniform holding a bottle of champagne and glasses on a platter.

"Another glass, sir?" he said, in a way that very clearly meant What the hell are you two doing – get going! Chuck let go of Sarah.

"Yes please," he said quickly, grabbing a glass and pouring it for himself. Downing it in one gulp, he ignored Casey and Sarah's surprised and slightly reproachful looks.

"Chuck, watch it, okay?" Sarah said quietly.

"We're portraying a drunk couple going to make out, aren't we?" Chuck replied, unable to control the annoyance in his voice. "I'm method acting." He downed another glass before Casey took the bottle and left, grumbling something about nerds and fancy parties.

Sarah looked at him for a moment as if studying him, frowning a little. "Are you okay, Chuck? You can head home now if you're not feeling up to it."

"I'm fine," he snapped, feeling somewhat like a pouting child and wishing he'd had more than two glasses because he wasn't feeling buzzed at all.

Sarah eyed him for a minute more before nodding. "Okay. If you say so." The playful air around her broke as definitely as if it had been shattered glass. She was all professionalism now, barely looking at him. Chuck put the glass down on some table and thought that that suited him just fine. "Shall we?"

The switch was just as sudden and complete as the first time. Sarah looked at him through her eyelashes, her smile slow and unbelievably seductive. Chuck swallowed, torn – as usually – between desperately wanting to kiss her and wanting to run for the hills. She trailed her fingers up his chest and leaned up to kiss the corner of his mouth. "Come with me, Mr. Carmichael," she whispered hotly in his ear. His knees went suspiciously weak.

They made their way around the edge of the ballroom, fingers twined together, Sarah shooting him fleeting and unbelievably sexy glances from time to time. Oh what he wouldn't give for this not to be a lie.

Near one tall, arched doorway into a candle-lit hallway, Sarah turned to face him, startling him out of gazing at the open expanse of her back. She raised her eyebrows at his conflicted look. "Chuck, are you sure you're okay? Because I can find a way to do this on my own."

"I'm fine," he said, starting to walk ahead of her into the hallway. The candlelight flickered on the yellow walls.

"Pardon me, but I haven't had the pleasure of greeting you," said a voice from behind them. Chuck turned and barely contained the look of utter shock on his face.

It was Valentine. The tall, dark haired man was more handsome close up than Chuck had judged before, when he had seen him on the yacht, and he was fixing his megawatt smile completely on Sarah. She smiled back brilliantly, dropping Chuck's hand to hold hers out to Valentine.

"Sarah Walker, Mr. Valentine. And let me say what a fabulous party this is and happy birthday!" Chuck gritted out a "Happy birthday" but somehow he guessed that Valentine wasn't listening.

"It's a pleasure to make your acquaintance, Mrs. Walker," he said, bringing her hand to his lips, his eyes never leaving hers. Chuck bit back the indignant noise in his throat.

Sarah blushed as her voice faltered. "Oh, we're not married." "This is my date, Charles Carmichael." She turned and smiled at Chuck, her gaze pointedly saying Don't freak out.

"Mr. Carmichael, it's a pleasure." Valentine was noticeably less friendly when he greeted Chuck, who put on what he hoped was a confident, superior smile.

"Happy birthday, Mr. Valentine."

"Thank you, thank you," Valentine said with another smile aimed at Sarah. "Now, if I might ask, why were you two coming this way? Were you about to leave? Because I couldn't stand you two leaving my party so early. The night is young!" He didn't look at Chuck once as he said this, and his hand was still holding Sarah's. Chuck clenched his jaw.

"Oh, I was just trying to find the restroom," said Sarah, recovering neatly with a dazzling smile. Was it really necessary that she completely trap Valentine in her charm as well?

"There are three in this wing of the house," Valentine said with a small laugh. "If you'd like, I can show you where one is." His hand left hers, drifting up her bare arm to her shoulder, where he gently stroked his thumb back and forth.

"Oh, that won't be necessary. But thank you," she replied politely, the brilliant smile still on her face. For one weird moment, Chuck wished she wasn't as gorgeous as she was.

"Then, maybe you'd like a tour of the mansion?" His voice was low and suggestive, his eyes even more so. Sarah paused like she had been caught off guard – how could she have been caught off guard after the rest of their conversation?! – and blinked. She shot a glance at Chuck, who was silently fuming off to the side, but he couldn't read what the look meant. Was she asking for his permission or something?

"I – " she started, but faltered. Something hot flooded Chuck's veins and he grabbed Sarah's hand, dragging her away from the rich birthday boy and down the hall.

"Sorry, nature calls," he yelled over his shoulder. When they rounded the corner, Sarah wrenched her hand out of his grip.

"What the hell was that?" she snapped, her eyes furious.

"I might ask you the same thing," he said angrily. "Did you have fun seducing Valentine back there?"

Her cheeks colored. "Seducing? I wasn't seducing him, I was trying to get him out of our way before I realized that it might be easier to use him to search the mansion instead of you because you were acting weird." She moved restlessly as she spoke, as if she couldn't hold herself still. "Also, 'nature calls'? What was that supposed to mean?"

"You know wha – nothing. And I told you I was fine!" Yelled Chuck.

"Keep your voice down!" she hissed angrily. "You may have just ruined our only chance to look around this mansion without drawing too much attention to ourselves." She sighed in resignation and raised her hands to run them through her hair before she remembered that she had a fancy hairdo and couldn't. They dropped to her side awkwardly. "I'll go get Casey and we'll figure something else out."

"If you hadn't drawn so much attention to yourself in the first place, none of that would have happened!"

She whirled to face him. "What? I was not drawing attention to myself," she said defensively.

"Yeah, you were! With your, you know," he waved his hand in her general direction. "And – and that dress, and your – you know what, never mind." He turned and walked down the hall, deeper into the mansion. "I'll just do this myself."

"Chuck, stop it." She grabbed his arm – hard. "You're going to go back to the ballroom, find Casey, and get out of here. I'll find Valentine, get a tour of the mansion and try to find out where the smallpox might be." He saw her swallow.

"Sarah, you know exactly what he meant by 'tour of the mansion' and it had nothing to do with 1920s architecture," Chuck replied. "And how are you going to know if something if important? You need me there to flash on things." Sarah was clenching her jaw tightly, but she didn't reply for a moment and Chuck knew he had won this round.

"You know, you're being uncharacteristically difficult tonight," she snapped. Chuck was surprised – usually she wasn't one for sniping remarks. "This is about saving the country and maybe even the world, remember? Union Station? Millions of people?" Her voice rose from a carefully controlled whisper to an angry yell. "What is wrong with you tonight, Chuck?"

He opened his mouth and then closed it, at a loss for words. As shameful as it was to admit, he had completely forgotten about the smallpox. He'd forgotten all he had said the night before, when he'd been so convinced that they had to do anything and everything to save their country. Chuck wasn't particularly patriotic, but there was no way he would stand by if millions of people were going to get sick and die.

But Sarah had made him forget all of that. She was beautiful and charming and deadly had flirted with a handsome billionaire and he had gotten so jealous that nothing else had mattered in that moment. Millions of lives hadn't mattered in that moment.

Chuck swallowed and Sarah raised a hand to her face, sighing. "I'm sorry. I shouldn't have said that." Her voice was much quieter and more than a little regretful.

"No. You were right," he replied in clipped tones. "We're here. We should look around." He made himself look at the wall.

"Okay," she said slowly. "If you're sure."

"I'm sure." He walked down the hall and heard her follow him a beat later.

They didn't say anything as they walked quickly and quietly down the hall, going into each room and doing fairly random sweeps. Chuck didn't really expect to find much on the same floor of the house as the ballroom – if you're going to have smallpox in your house, they'd better be well protected – but he didn't want to argue with Sarah. In fact, he didn't really want to look at her that much either. Something was festering under his skin – jealousy, anger, frustration.

Sarah caught the skirt of her gown on a corner for the third time and sighed in frustration. Chuck stopped short and turned to her. "We're never going to find anything in here. No one in their right mind would keep smallpox unguarded!" he said.

She looked irritably at him. "We can't take on armed guards just the two of us anyway, Chuck. Right now we're just looking for clues about shipping schedules or…anything." She muttered something under her breath that Chuck didn't catch and headed for the door. "There's nothing here. Let's try the next room."

As she reached the doorway, Chuck right behind her, they heard voices in the hallway. Sarah whirled toward Chuck, a mildly frantic look in her eyes, grabbed the front of his tuxedo, and pulled him to her. Their lips slammed together as she pushed him up against a wall, her mouth opening to his and her hands holding the sides of his face in an iron grip.

The voices paused outside their doorway and then awkwardly continued, fading down the hall. Sarah pulled away slowly, meeting his eyes for an instant before looking away. She took a step back.

"Sorry."

"Don't worry about it," Chuck said in a heavy voice, looking back into the room to avoid her eyes. Then he saw something they had missed before. There, under a table in the library, was a small box. Brow furrowed, Chuck went to pick it up. There was a small piece of paper tied on top of the box, and all it said was 'Darkwind'.

"Sarah," he said. "I think you should see this." Slowly, as she ran over, he untied the strong holding what looked like a small gift box. Pulling the top off, Chuck sincerely hoped that there wasn't a bomb or smallpox inside.

It was a key card. But as Chuck laid eyes on it, his vision blurred and suddenly he was looking at a heart-shaped candy box, a dozen long-stemmed roses, a hospital, a photograph of a man, a harbor full of ships, several confidential files and a golden retriever puppy.

Blinking out of it, Chuck handed the box to Sarah.

"What is it, Chuck?" she said. Chuck looked down at her and saw that she had on her ready-for-anything face on, her gaze intense and focused on him. "What did you see?"

He swallowed. "That key opens the door to the vault in the basement where the smallpox is being stored. There's an intense security system but no guards, because nobody was supposed to get their hands on this key."

"Why not? It was at a party full of people. Anyone might have stumbled in here."

"That's because the key was meant to be picked up here in this room while the party was going on. Nobody would notice one person slipping out of a crowded room."

"So…Darkwind is here. At this party." Sarah paused for a moment to take that in before hiking up the skirt of her gown – "What are you doing?!" Chuck yelped – to take two throwing knives off of the holder strapped to her thigh.

"Don't have your gun?" Asked Chuck sarcastically.

"No place to hide it," she said tersely, holding up her wrist to speak into her bracelet. "Casey, track us and get to our location right now. Darkwind is at the party."

"Hm. Pity. No one was supposed to know that."

Chuck jumped and whirled around. There, standing in the door, was the tall, brown-haired man from the photo in Chuck's flash. There was a scar running along his jaw that stood out white from his tanned skin. He was holding a gun and aiming it at Chuck's chest.

Darkwind.