Peggy, Thompson and Sousa undercover at a costume party! (I was prompted by the lovely glitnir-gebo over on Tumblr)

A/N: I apologize if this got a little long and rambly... I was way too proud of myself for picking Thompson and Sousa's costumes and then I finished at like 1am and it was just generally a mess. However, I think there's still plenty of cuteness in here for you to enjoy! Let me know what you think.

"I'm sorry, you want us to what?" Peggy asked, cocking her head to the side even though Sousa knew she had heard perfectly well.

Thompson scowled and tugged at his cuffs. "This party is the only time anyone gets into Robinson's estate all year. We're going to have to go in as guests."

"And… the theme is movies?" Sousa asked tentatively. He, too, knew precisely what had been said, but he knew how much Thompson disliked the idea and making him repeat it was a little amusing.

"We'd better do something popular and recent," Thompson warned.

"Ideally our costumes would hide our identities, too," Peggy mused. "I may have an idea."

Sousa was struggled to keep from beaming. His fingers tapped excitedly against his crutch as an idea sprang fully-formed to his mind. "I have just the thing."

Thomson smiled a little to himself. "I might be able to throw something together…" The surprisingly pleasant expression slid once more from his face. "Be back at the office at seven, sharp. We can change here and take one of the cars to the party. I expect both of you to smuggle in as many toys as you can—we don't know what it'll take to get Robinson to talk."

The two agents nodded before walking briskly away, perhaps a little too quickly and with a little too much enthusiasm.

"Come on, Peggy, how long are you going to take?" Sousa called into the locker room. He was anxious for her to see his own meticulously-crafted costume.

"Just a moment!" the response echoed out.

Sousa sighed and leaned heavily onto his crutch, which he had managed to transform into a large maroon umbrella with a curved handle. He was wearing a black coat over a creamy orange vest with a yellow ascot. His khaki slacks were creased to perfection and he held an enormous blue top hat in his other hand.

He finally heard the click of his colleague's heels approaching. "Jiminy Cricket, Daniel!" she joked as she came into view and saw his costume, but he was frozen and didn't respond.

Peggy had donned a wide-brimmed white hat over a curly gold wig. Her dress, a decadent confection of lace, false flowers, and white chiffon, hung easily off her shoulders and swept the floor behind her. AS ridiculous as it could have been, it somehow fitted with her elegant, angular face and confident stride. She raised an eyebrow when Sousa still hadn't responded several seconds later. "Cat got your tongue, Agent Sousa?"

He cleared his throat. "Who are you dressed as?"

"The second Mrs. de Winter from Rebecca," Peggy explained as though it should be obvious, "when she dressed like one of the mansion's portraits for the costume ball." He had never seen the movie but he nodded as though this sounded familiar. She swirled the skirt a little. "You wouldn't believe how many weapons I can fit under here."

Sousa shook his umbrella, forcing a smile as he finally broke from his shock. "I've got a few, too." He almost offered her his arm before deciding against it. Come on, Agent, just because you're not in the office it doesn't mean that this is any better an idea. Remember what Krzeminski said. "Shall we head up and see what Thompson's got?"

"Wouldn't miss it," she responded with a slightly malicious grin that made him grip his crutch tighter.

There was no light under the office door as they approached.

"Surely he's not late." The annoyance was evident in Peggy's voice. She put her ear to the door before entering, presumably out of longstanding habit, and pushed it open when she heard nothing.

Quick as lightning, a figure dressed in black darted out in front of her. Its face was swathed in dark fabric except for its steel-grey eyes. It brandished a whippy fencing foil and danced back and forth on its toes, clearly offering a challenge.

Peggy spun, her long leg keeping her well out of range of the foil as her immaculate white slipper impacted the intruder's jaw. Sousa was less than a second behind as he slid a pistol from his umbrella and cocked it, aiming the barrel at the figure's head in one smooth motion.

The figure let out a deep groan which betrayed its identity. "Damn it Carter, was that really called for?"

Sousa immediately dropped his weapon to his side. "Thompson?" He slipped it back into its hiding place, fingers shaking slightly in the wake of the adrenaline, and loped over to pull his colleague to his feet. "What are you doing?"

"Clearly not playing the hilarious joke I intended," he grumbled, allowing himself to be pulled up. He rolled up his mask and poked at his jawbone, where a shining purple bruise was already developing. "Jesus Carter. You've never seen Zorro?"

Peggy, who had been sensibly hanging back, let out something very similar to a guffaw. "You dressed as Zorro?"

Thompson stiffened like an offended hen. "It's a good film. What are you, a princess or something?"

"I'm the second—oh, never mind. Let's just get to the party and get what we need from Robinson."

Sousa noticed that she was eyeing Thompson's face carefully, however. Peggy might talk tough but he knew that she was probably beating herself up for not recognizing her coworker. The three of them made their way to the elevators and downstairs in full costume, Thompson's slowly-swelling face hidden once more by his mask.

The party was easy enough to get into, though somehow it worked out that Peggy was the one to lead them, one on each arm, through the doors.

"Ah! The Second Mrs. de Winters!" the host smiled, bowing them in.

Peggy laughed lightly, emanating charm from her sparkling eyes. "I'm glad someone recognized me! My friends here aren't quite up to snuff on their film."

The man chuckled as they passed him. Once they were a safe distance away, Thompson tugged his arm from her grasp and Sousa belatedly followed his lead. "All right Carter, you've had your fun. Let's get to work."

"Gladly." She swept off into the crowd, still with that champagne-stylish smile.

Once Sousa had torn his gaze from the frothy skirt which swayed with her stride, he looked to Thompson. "She'll probably do better on her own," he offered. "Woman's charms and all that."

Thompson scowled, but his expression quickly turned guilty—at least, Sousa thought it did. It was hard to tell behind the mask. "Maybe. I guess she's shown she can hold her own." He fingered his jaw once more and visibly winced.

"Come on," Sousa said, urging him along with his umbrella crutch. "Let's check out the buffet. Maybe Robinson will be there."

It was a beautiful party—a soirée, rather, as Thompson corrected him sharply. The correct terminology was essential to blending in with the rest of the guests. The ballroom was Victorian, Sousa thought, with ornate detailing along the walls and stunning chandeliers which cast chips of light over the guests. Women in all manner of costumes swirled across the dance floor with their equally diverse partners. He recognized Dorothy's blue gingham dress and pigtails and found that the character had lost all innocence due to her association with the ruthless assassin of the same name. There were a few of the usual Cleopatras and Scarlett O'Haras. At least three men wore approximations of Captain America's star spangled armor and Sousa felt a sting of pity for Peggy each time he saw them. He couldn't even imagine what it must be like to see people using her dead love as an amusing costume.

Sousa grabbed a glass of champagne, then another. His thoughts kept turning towards his colleague and her ambitious costume, her smile and her stride and oh lord he wasn't supposed to be thinking like this.

He tried to keep his eyes on the room, especially since he had the sneaking suspicion that Thompson might actually be able to read his mind, but the other man seemed like he was actually focusing on the task at hand to maybe he was safe for the time being. Besides, his oversized blue hat kept sliding down over his eyes, which made it difficult to concentrate.

They made polite conversation with a few of the guests and inquired casually after their host, but to no avail. After several circuits of the room they were just about to start searching the rest of the house when Peggy swept up to them, a smile on her lips and a flush in her cheeks. "Why gentlemen! Fancy seeing you here."

"You seem like you're having fun," Thompson said drily.

"Actually," she said, narrowing her eyes to imply that her words held more than their literal meaning, "I thought I might leave soon."

Sousa couldn't help but smile. It seemed that she was handling things on her own after all.

"What's stopping you from leaving now?" Thompson asked almost urgently. One of the women turned at his apparent rudeness and the three of them sank back out of the crowd. "Waiting to compliment the host on the party?"

"Precisely." Peggy smiled. "I thought that if I could convince one of you two to dance, I could keep an eye out for him in the process." She looked at Sousa first—not just a passing glance but a real stare with a question in her eyes.

He cleared his throat. He sounded embarrassingly like a car trying to start with no gas in the tank. "That's awful nice of you, Peggy, but I'd just step on your toes." He tapped his shoe with his umbrella and she looked almost startled, as though she had completely forgotten about his leg. Without missing a beat, she turned her attention to Thompson, who was fidgeting with his outfit. It must have been getting stuffy by that point in the evening.

"Perhaps the great Zorro would care to dance?"

"He wouldn't," Thompson said in a low voice, but sighed and stepped forward. He knew Peggy well enough by now to realize that this was no whim of convenience; if she was asking him to dance on a mission—or any other time, for that matter—she had a damn good motive.

They stepped out onto the floor together and were quickly lost in the swirling mass of dancers. Sousa shifted his weight from leg to leg and waited for them to flicker back into view, the tall, black figure and the floaty white one. They looked good, he realized. However much Thompson was going to complain about this later, they matched each other's time with a graceful ease. It almost looked like they had danced before…

Sousa took a large drink of champagne and pushed those thoughts out of his head just as a pretty young woman dressed like a flapper edged over to him. "Hi there, Mister!"

He couldn't help but smile at the enthusiasm in her voice. "Hello."

"I love your costume!" She grinned. "Most people wouldn't think to add the umbrella."

"It's… important, yeah," he said, feeling for some reason like he was lying.

Before the conversation could go any further, three figures burst from the crowd, scattering startled guests and knocking over a small table of refreshments. Peggy and Thompson were in hot pursuit of an unfamiliar blonde woman in expensive clothing.

"Daniel!" Peggy yelled, her skirt billowing out behind her, and he took two limping steps towards their path before swinging his crutch with enough force to fell a horse. The woman shrieked as it smashed into her shins and Sousa belatedly realized that that level of gusto was probably uncalled for.

Thompson ripped the mask from his face as he slid to a stop and knelt above the prone, groaning woman. "We're SSR!" Sousa assured the crowd, holding up his badge as his colleague handcuffed her. The woman he had been talking two just seconds before glanced from the woman on the floor to Peggy, who was trying to be surreptitious about freeing a pistol from the lacy tangle of her skirt, to Thompson and his bruised face, and finally to the newly-revealed crutch which Sousa now leaned heavily against. Even now, a year after the war ended, two steps without the damn thing were enough to cripple him for the rest of the evening.

The girl took a step backward and melted into the crowd. He sighed angrily and shoved his badge back into his coat. "I assume this is a situation where you fill me in once we get back to HQ?"

Peggy flashed him a guilty look. "Sorry Daniel. It's a long story but we've got our woman."

Thompson finished handcuffing "their woman" and hauled her to her feet. He waved over his shoulder at the gathered crowd. "Thanks for the party, fellas. Let's do it again soon."

Peggy rolled her eyes and waited while Sousa ducked to retrieve his enormous blue hat from the floor, then followed him out. At least when she walked behind him she couldn't read the pain on his face.

Into the contained back of the car went the still-mysterious woman. Thompson beat Peggy to the driver's seat but she slid into the bench seat in the back alongside Sousa rather than claiming the front. Thompson put on the radio and they rode in tired silence for a few minutes.

"I'm impressed by your costume," Peggy finally said, adjusting her massive skirt.

"Finally," Thompson said, half turning.

Peggy laughed—actually laughed, as though they were just friends returning from a party. "I meant Daniel." She turned to Sousa. "How did you throw that together so quickly? And the umbrella?"

He shrugged to hide his embarrassment. "My niece loved the movie. I promised I'd take her out for Halloween this year and dress up."

"Sousa," Thompson interjected, "it's May."

"I know. It's just, I wasn't here last year…" He trailed off and they all knew exactly how he felt. The missed years with loved ones would never be forgotten, even if those loved ones were still around.

"I still think it's impressive," Peggy said after a few more moments.

"Thanks." Sousa straightened his mouth with some effort. "So let's hear about her." He jerked his head towards the back. Trying to have these normal conversations with Peggy took more energy and thought than he had available to give just then.

Thompson laughed loudly. "Carter seduced her?"

"What?"

Peggy turned to him but glared at the back of Thompson's head. "This is Robinson's wife. I was talking to her at the party and found out that she was really the one running things. She implied that she might be interested in a… covert meeting with me later in the evening, but of course I needed to get the information as quickly as possible."

A strangely amusing thought connected in Sousa's mind. "So you were dancing with Thompson to make the suspect's wife jealous?"

"It worked!" Peggy said, her voice a mixture of pride and something else that might have been irony. It was hard to tell when he couldn't see her face clearly. "She dragged me off to the library and I managed to get a few things of use out of her. Then she came to her senses, realized her mistake, and ran."

Sousa laughed in spite of himself. "See Thompson? I told you she could get by on her women's charm without our help."

"I don't think you could have foreseen it like this, though," Thompson argued from the front seat.

"'Women's charms'?" Peggy asked at the same time.

Sousa leaned back. "Well you two bagged her in the end, I guess." He yawned. "I suppose now we've got to stay and interrogate her."

"Nah," Thompson responded. "I think a night alone with her thoughts might do her some good. We'll put a guard on her and head home for the night."

"I for one can't wait to get out of this bloody costume!" Peggy exclaimed. Sousa looked at her sideways.

"How did you manage to get your costume in the space of a day? It seems pretty specific."

"A girl has her ways."

Sousa smiled and shook his head. "Fine. And I'm not even going to ask about the masked vigilante here." He nodded to the front seat. Somehow the laughter was helping the steady ache in his leg that throbbed with his heartbeat and he almost wished the drive would never end.

Thompson sputtered something unintelligible and he and Peggy laughed.

The ride did end eventually, of course, with them locking up Mrs. Robinson and heading into the Men's Locker Room to relieve themselves of the burdens of their costumes. Peggy changed on the other side of the partition as she had before the Russia mission all those months ago. The memory brought a flush to Sousa's neck that could, fortunately, be blamed on his stifling ascot. She and Thompson tossed veiled insults back and forth like a ball while he listened and tried to keep his weight off his bad leg. All too soon they were standing outside the building, nodding farewell and striding off to catch their separate cabs. He limped down the sidewalk, his bitterness having long since evaporated into resignation, and glanced back at his disappearing colleagues.

You'll see her again tomorrow, idiot, he reminded himself, and forced his crutch into another arc so he could continue his progress. Try as he might, though, he knew he wouldn't be able to keep the beautiful figure in the old-fashioned gown out of his dreams…