A/N: Inspiration hit me like a brick today, so have some pre-series Caitlin and Wells.

Disclaimer: Don't own them.

When Dr. Wells walks into the lab, he seems almost...giddy. There is an expression on his face Caitlin has only ever associated with scientific breakthroughs and fantastic discoveries but he's coming from home so unless he solved some mystery of the universe over morning coffee – the possibility of which she doesn't quite discount – something quite spectacular must have happened.

"If you gather around, I have an announcement to make."

The scientists look at each other with differing amounts of suspicion but follow the instructions as he steps behind his desk and looks around the room with a smile hovering around the edges of his mouth.

"As S.T.A.R. Labs has grown considerably in the past years and our particle accelerator has been attracting some attention, I am pleased to announce that we have been noticed by a formidable facility. In Europe."

A small murmur breaks over the room and he seems quite pleased with having piqued everyone's interest.

"I can hear the braver ones whisper out the correct answer. It is indeed CERN and they have extended an offer to visit their facilities as a part of their partnership program and collaborate on many of the scientific work we do here. So you may all congratulate yourselves for this feat as none of this could have happened without your contributions."

Caitlin watches as everyone claps and a genuine happiness falls over the room. She, too, is surprised and amazed; CERN is no small feat to achieve and while her work isn't directly related to the reason they've been invited, attention to the lab is always welcome.

She catches Wells' eye over the crowd and the smile he bestows on her is genuine and warm. He raises his hand and gestures for her to come over and she goes, slightly embarrassed that he singles her out from the room but also wanting to congratulate him personally as well.

"I knew there was a reason you were so happy this morning." He is even more cheerful up close but her remark makes him raise an eyebrow.

"Am I normally not happy then?"

"Well, it is not like you are sad. But there is a certain magic in seeing you so...relaxed and pleased with yourself. And this is quite an honor, so I think the entire lab will be talking non-stop about this."

He smiles and nods. "Yes, they will. I didn't say this out loud but CERN has also extended us the invitation to visit their facility for their 45th anniversary gala, held in Geneva."

"All of us?"

"Me as the head of the lab and a guest."

Caitlin turns to look at the room, ready to suggest a suitable candidate. "Well, I think Dr. Lang or Dr. Meekum would relish the opportunity to visit CERN. Or maybe Cisco, he would love to-"

"Actually, I was thinking you."

He stops her mid-sentence and when his words register, she looks at him, astonished at the suggestion. "Me? But I'm not even a particle physicist and I just received my doctorate and I don't have nearly as much to do with the particle accelerator and-"

"Caitlin." He interrupts her flow of words gently but firmly and his hand closes around her elbow to fully capture her attention.

"You have the least amount of experience out of anyone in this room and that is precisely why you should come; I don't think there is anyone else who would appreciate it more than you. You are remarkable and brilliant and your work is very important."

His blue eyes bore into hers and she is rendered speechless, captivated by his words and how convincing they sound.

She finds herself nodding before she actually considers it. "Okay."

Geneva in September is breathtaking. Caitlin takes everything in as much as she can: the views, the people, the atmosphere, their hosts, and enjoys every meeting they have thoroughly. Wells doesn't seem as interested in all of the achievements – he more than once leans closer to her to whisper It's like they think we don't actually do science in the US – but to her surprise, doesn't actually antagonize anyone and braves through all of it with at least a neutral expression.

Cisco was overjoyed when she told him she was going to Geneva with Wells, showing no signs of jealousy or making any snide remarks. Instead, he gave her explicit instructions which CERN-logo merchandise she should bring him – A sweatshirt and a pen and, oh, take some pictures of their large hadron- Cisco, that would be industrial espionage – and was even more excited than she.

Truth be told, she doesn't still quite understand why she's on this journey. She enjoys it fully, the science, the scientists and all the surroundings but logically, she would've been one of the last choices to merit a visit to CERN.

Then again, Dr. Wells' decisions don't always make sense but they're never senseless either.

They are invited to participate in the big gala, celebrating 45 years of CERN and as she walks up the stairs to the event, she feels rather nervous and self-conscious, smoothing her dress and refraining from the urge to touch her hair one more time.

Which is silly because she's met most of the people there anyway and Dr. Wells will be there as well and this has nothing to do with the fact that his presence is what actually makes her nervous.

Absolutely nothing.

The midnight blue gown she took with her still fits perfectly – and no one needs to know it was a bridesmaid dress once – and it's tasteful enough to work in a ballroom.

The women around her seem to wearing dresses cut from silk and pure gold and her nerves don't abate one bit.

She closes her eyes for a moment, taking a deep breath and when she opens them, Wells is standing right in front of her, clad in a tuxedo tailor-made for him.

He takes her in from head to toe and his gaze feels scrutinizing but also admiring in a way she has never seen him look at her. When he meets her gaze, he smiles softly.

"You look beautiful, Caitlin."

"As do you."

He offers her his arm and she gladly accepts it, walking into the grand ballroom together, ready to face the evening.

She spends a lot of it mingling with the different scientists, talking about discoveries and breakthroughs and while she doesn't spend too much time with Wells, she can almost always sense when he is looking at her, even from across the room and meets his eyes every time with a small smile.

When she's had four glasses of champagne, she finds him again and, feeling a bit daring, offers something she knows he doesn't quite like.

"Dance with me."

To her surprise, he doesn't outright decline – because she knows how much he doesn't like to dance, has tried it more than once – but puts down his own glass, takes her by the hand and leads them to the dance floor.

Caitlin feels victorious for about three seconds until he takes her in the correct dance hold and when his hand lands high on her back, thumb almost caressing her bare skin, she instantly knows that this might not have been one of her brightest ideas.

"Ready?"

And before she can ask anything, he starts guiding them across the floor in a waltz, effortlessly leading them – because she can waltz, thank you very much – while looking at her with an expectant expression.

"So how do you find Geneva, Caitlin?"

"Fascinating, Dr.-Harrison."

She's never called him by his first name – though it was one of the first things he asked of everyone and yet she's avoided it because she feels it's disrespectful in a way – but it tumbles over her lips this one time and she can tell it startles him, just a bit.

His only response, however, is to slightly tighten his hold on her and smile slightly but he makes no further comment.

He dances with her for four turns, making small-talk about CERN and the program, about S.T.A.R. Labs – and his hope that Cisco hasn't completely blown it to pieces – but all Caitlin can focus on is his warmth and his strength around her. The champagne in her head isn't helping much but she decides it's a good thing, rather than a disadvantage and when they conclude with another waltz, she is resolute.

"Come on, let's get some air."

This time, Wells lets her lead and they exit through large glass doors onto the balcony. She lets go of his hand then and breathes deeply; she really did need the air but instead of clearing her head, it is making her current state of mind even more sharp.

"Are you feeling alright, Caitlin?"

She opens her eyes and just like before, he is standing in front of her but so much closer and his eyes so much bluer and she doesn't even quite think – or chooses not to because this is instinct and want and desire – as she slides her hands up the lapels of his jacket and tugs him closer to kiss him.

So what if she's had a crush on him since before he asked her to work with him? So what if he is her boss and this is a terrible idea? In that moment, she has no space for any of those considerations but only a burning need to find out if he's a good kisser, like she's sometimes – always – imagined and oh, god.

He kisses her back for a moment and she has the fleeting thought that he must not be as surprised as she would think before he steps back from her and puts distance between them.

"Caitlin." If she was looking closer, she would see that the expression on his face is regret warring with desire but she can only see rejection and isn't quite ready for how that stings.

"We shouldn't be doing this."

She hopes she doesn't let her face fall as much as she can feel the vice constrict around her heart but nods and clears her throat.

"Yes, you're right. That was very unprofessional of me and I apologize, Dr. Wells."

He makes a move as if to touch her once more but his hand stops mid-air and an impenetrable mask falls over his face. "I'm sorry."

She doesn't know what he's sorry for: rejecting her or not wanting her or her having these stupid feelings but she makes herself not care.

"It's fine."

And she proves that by asking Ronnie Raymond out on a date as soon as they're back because she doesn't wallow, she moves on.