Natasha woke to an empty bed. She couldn't help the twinge of disappointment. Neither she nor Melinda were big on holidays and celebrations, but she had expected… something. A good morning kiss and a "Happy Birthday" before they got up and ready for work. But apparently that was not going to happen.

Maria had an op for her today. As Natasha approached her office, she saw Melinda coming out. Melinda didn't seem to notice her though, her nose was buried in a file as she turned the corner and headed down the hall in the opposite direction. Natasha pushed away her dismay. She stepped into Maria's office. "You have something for me?"

Maria stood and handed her a folder. "Yes," she said. "We cleared out a Hydra base last week. The initial team stripped it, but one of the operatives we captured gave us intel that there may be a hidden office we missed. I want you to go and retrieve any intel."

Natasha nodded curtly. "Solo entry or with a team?"

"Solo," Maria answered. "After we swept the building, we put up surveillance around the area and haven't seen anything, but I'm sure Hydra is watching to see if we go back to it. If they think we missed their data center on the first sweep, I don't want them to realize we're looking at the facility any harder."

"I'm sneaking into an empty facility."

Maria grinned. "Pretty much. We figured you could use an easy mission today. Get home early to your girlfriend."

Natasha produced the expected smile in return. Melinda had had a lot on her mind lately. Between leaving bed early this morning and not seeing her in the hall, Natasha strongly suspected that minor details like birthdays had slipped her notice.

"Mission details are in the file," Maria said. "If you have any questions, ask Hand; she's running control."

Natasha knew a dismissal when she heard it.

A few hours later, Natasha crept into the abandoned Hydra base, inside an old warehouse. She noted the Shield cameras around the perimeter, as well as a few others that were not Shield issue. Maria was right. Hydra was continuing to monitor their base. She stayed out of sight of all the cameras, Shield and Hydra alike.

The minute Natasha stepped into the building, her senses were on high alert. According to Maria's file, nobody had entered the warehouse since the Shield team took down its Hydra occupants several weeks ago. But a cursory examination said otherwise.

A faint smell of gasoline hung in the air. Someone had driven a vehicle through here, probably within the past few hours. Dried mud tracks crisscrossed the concrete floor, but one of the tracks, coming from the far side of the warehouse, still glistened with moisture.

Natasha stood completely still and silent, even halting the sound of her own breath while she listened. She heard movement. Somewhere in the building, someone else was already here.

The intel in the hidden office was her first priority. That was her mission. Infiltrate, retrieve intel, get to the extraction point. The presence of potential hostiles did not change the mission parameters. But they did perhaps complicate it.

She melted into the shadows and slipped silently through the building, toward the unremarkable warehouse office. A staircase led up to a catwalk overlooking the warehouse floor, but Natasha wasn't looking for stairs up.

She found the entrance just where the file said it would be, hidden behind a wall panel six feet to the left of the desk. Natasha examined the wood paneling briefly, looking both for the trigger to open it and for any potential booby traps. She found the release and pressed.

The door swung open. Natasha listened again. The rustling movement she'd heard earlier was closer now, but if stilled the moment she opened the door. An oddly sweet smell swirled up the stairs to greet her.

Natasha pulled a small scrap of cloth from her belt and shook it out. Stark Industries had come a long way with gas mask technology since the old days of rubber and glass that encased the entire face. She looped the ends over her ears and breathed in. The smell was gone now.

Natasha palmed one of her guns and pressed against the wall. She descended slowly into the dark basement. The gas mask protected her from whatever that sweet smell was, but she hated having any of her senses muted in the field. Her eyes adapted to the dim light that filtered down through the open door at the top of the stairs.

At the foot of the stairs, Natasha found a light switch on the wall. She turned it on. If anybody was waiting for her in the dark, they obviously would have been prepared with night-vision goggles, so she wasn't going to lurk in the dark and leave herself at a disadvantage, especially with her sense of smell muted by the gas mask.

The basement seemed completely empty, save for a row of computer servers connected to a monitor against the far wall. Natasha looked around. Four solid walls, a concrete floor, and steel beams supporting the warehouse floor overhead. No sign of any hostile presence.

She stalked forward, warily moving toward the computer terminal. When she reached the center of the room, she heard a loud pop to the right and spun to face the formerly blank wall. A banner unfurled, swooping down against the wall:

Happy Birthday, Natasha!

Love, the Avengers & Shield

(Please don't kill us)

Natasha turned, gun still in hand, to scan the room. The wall behind her flickered as someone stepped through the holographic projection. Melinda.

Melinda smiled. "Happy birthday, honey."

Natasha did not let her guard down. This could be another Agent 33 issue, although if it was, it was the strangest scenario she'd heard of. Melinda walked over and pulled her gas mask down to kiss her.

Natasha blinked, then kissed her back. Hydra might be able to replicate someone's face, but they couldn't copy their smell, their taste, the feel of their lips against hers. This was 100% Melinda.

Natasha returned her gun to her belt and then embraced Melinda. One arm wrapped up around her back and the other dropped to grope her ass. Melinda shivered and bit Natasha's lip in response.

"Well there's something you don't see every day." Tony Stark's voice broke into the moment. Natasha broke away from their kiss just enough to turn and stare at him. She flicked him off with her free hand.

"Speak for yourself," Maria said, as she emerged through the holographic wall. She tapped a code into her phone and the projection vanished, revealing the rest of the team, along with a giant cake (the source of the sweet, not-noxious-gas scent that Natasha had detected). "You've never had to live with them."

Melinda pulled back, unfortunately dislodging Natasha's hand in the process. "Last year when I tried to organize a party, you kept shooting down all of my ideas. Thought it would be better to surprise you this year."

"That'll teach you to be a jerk to your girlfriend," Clint added. "If you were nicer, we wouldn't have to organize a surprise party that comes with the risk of you killing us all before we can say "Happy Birthday."

"Speaking of which," Pepper jumped in, "I believe our stripper is still waiting for his cue."

Melinda leaned in and whispered into Natasha's ear, "Darcy convinced Thor that it was customary to have a stripper at birthday celebrations. I know Jane told him otherwise, but I think he just liked the idea."

"One," Darcy started counting, "Two, three…"

"Happy Birthday!" everyone shouted. Thor jumped out from behind the computer desk.