A/N: Randomly popped into my head. You know, plot bunny. Set around Season 5.

Tony woke alone that Saturday morning to a pile of tangled sheets and a splitting headache.

It took him a moment to get his bearings; at first he wasn't even entirely sure he was in his own apartment. But once he figured that out, he slowly tried to do a sit-rep. There were questions to be answered, like:

Why didn't he remember anything from last night?

And…

Wait. He heard the shower turn on.

Just who was in his shower?

He could hear the water running. Oh, God how he hoped he hadn't brought back another waitress.

OK, he thought. I've got approximately four minutes to figure out just who I brought home last night before an awkward confrontation. I'm an investigator – time to investigate.

He started with his bedroom. Killing two birds with one stone, he began to make up the bed again. As he lifted the duvet he saw something silver fall onto the floor.

It was a small, empty square package with a circular indentation – probably from being sat on. He quickly grabbed his wallet from the nightstand. Where the very same little package had sat for months was now gone.

Alright. His relationship with the mysterious shower woman was a little more serious than he initially thought. Then again, though, if he did bring back a woman why wouldn't he sleep with her? He wouldn't just bring back a strange woman to have a sleepover, and he mustn't have known her, because he'd remember something like that, right?

Right?

He shook off that unsettling thought and tried to look around for more clues. There was nothing in the room that would prove the identity of the girl. No clothes, no ID, no phone, nothing. He looked around for his own cell, thinking perhaps that would lead him somewhere.

It did.

1 Unread Message.

Received: 3:47am

From: McGee

Hey tony abs wanted to make sure u guys got back ok. shes pretty hammered so shes gonna stay with me. hope gibbs doesnt find out. also her memory ran out on her phone so I think she used urs 2 take pics of the party.

"Wow," Tony thought aloud. "McGeek's grammar is usually perfect."

Then it hit him.

The office Christmas party. And Abby had taken pictures.

He scrambled to find the gallery, and find evidence. Anything.

They were mainly of the employees, and a bunch of casual acquaintances from other departments. Out of the forty or so pictures, he was only in a few of them. Pretty much all of them contained McGee or Gibbs, and one of the both of them awkwardly caught under the mistletoe, Gibbs giving everyone his death glare, and McGee just looking plain uncomfortable. Ziva only seemed to be in a few of the pictures too, which was weird, because she certainly wasn't camera shy.

After scrambling through them quickly, searching for signs of himself with a woman, he decided to look at things from a new perspective.

The pictures were taken chronologically, which meant they showed a timeline of some of his evening. The first picture was taken at around two, and the last one was at ten to three. He must have left at about three otherwise he wouldn't have been home before McGee texted him.

The first one was the geek himself and playing beer pong of all things, and Ziva was watching them with some kind of disapproving but slightly amused smirk. Gibbs looked like he was about to slap Tony. The next few pictures he could see his grey suit and also Ziva's green blouse in the background while Abby took pictures of McGee. That was the last of either of them.

But then he looked again. One happy snap of the Elf Lord getting head slapped also captured his arm and a wave of dark hair leaving the room. They don't come back until…the last photo, which was everyone. Though Tony's shirt buttons looked uneven, his tie was all weird and he had a certain expression on his face…one even the man himself could recognise. His heart rate rising, he looked over at Ziva who, believe it or not, was sporting a very similar expression.

He looked at the bathroom door. That couldn't be Ziva in there, could it? Surely he'd remember sleeping with Ziva?

No, he told himself. It can't be Ziva. You probably just had too much to drink…the picture isn't good quality anyway, and it's a small screen. You can't be sure what your face looks like.

He kept reassuring himself but as he shifted the duvet properly onto the bed, a garment of clothing fell out.

A blouse.

A green blouse.

A/N: TBC!