Fitzsimmons were already in the lab when May walked in at 7:30 am. They didn't seem to notice her take a seat at the bench, however, because they appeared to be in a heated discussion.

'Don't be so naive, Fitz!' Jemma berated in a carrying whisper.

'Oh, naive. Look around, Jemma, I'm not the one being naive!' Fitz hissed back.

'I'm not a damsel in distress, Fitz. It's my choice. You don't have to save me all the time.'

'Well, wouldn't that be nice. Maybe if you didn't willingly waltz into these situations I could-'

'Ughh Fitz!'

'Jemma, Don't-'

'May!' Jemma's voice returned to its usual bright tone, cutting Fitz off as she spotted May. 'I'm sorry, May, I'm needed by the director today but Fitz is going to spend the day amazing you with all the details about polymers, like the fabrics we use to make your clothes.'

Jemma shot one last look at Fitz, which was more a look of disappointment than anything else, and half-jogged out of the lab, her orange lanyard bouncing around wildly as she went.

'You wanna tell me why I need a day-long lecture about my clothes?' May said dryly. She was trying to ease some of the tension in the room, but Fitz wasn't having any of it.

'No, May, polymers aren't just about your clothes,' he said impatiently. 'They're in everything - all the materials of your weaponry, bullet-proof vests, even a lot of the Zephyr.'

Fitz sighed audibly and began fiddling with his computer. After much huffing and muttering under his breath, he pulled up a Powerpoint presentation and flashed it onto his screen.

May spent the next four hours listening it a rather irate Fitz explain polymer chemistry, with a large amount of gesturing and impromptu diagrams. She was surprised to find the material extremely interesting. Fitz was a good teacher, and had a good ability to explain complex ideas in simple terms, drawing analogies and making connections to the equipment that May used every day. She suspected that this skill was not one that Fitz was born with, but rather one that he was forced to develop through years of frustration from not being understood by anyone other than Jemma.

While educational, the whole experience would have been much more pleasant if Fitz wasn't in such a foul mood. His irritability made his speech faster and faster as the day progressed, and when May returned after lunch to find Fitz talking faster than ever in a thicker-than-usual Scottish accent, she put her foot down.

'Fitz.'

'-and the intermolecular forces between the strands provide additional tensile-'

'-Fitz!'

'What? he glared at her, annoyed at the interruption.

'You're talking faster than the speed of light.'

'That- that is ridiculous. Nothing is faster than the speed of light. It's not just the speed of light, it's the speed of causality, one of the fundamental const-'

'Fitz. Stop.'

Fitz stared at her.

'You want to tell me what's been bothering you? Because if you keep going on at the speed of-' May stopped herself just in time. 'At this speed, you're going to lose me completely and also end up with a very sore throat.'

Fitz swallowed. Now that she mentioned it, his throat was feeling a little sore and dry. He grabbed his mug of cold tea from the counter - a mug that had been neglected ever since Jemma had lovingly placed it there this morning - and swallowed several mouthfuls. This had the effect of simultaneously calming him down a little while also churning up a distinct feeling of guilt in the pit of his stomach.

'It's Jemma.'

'Of course it is.'

Fitz sighed and dropped into his chair, spinning it from side to side while fiddling with his green lanyard. 'She's got compulsory lie detection today.'

When he didn't continue, May prompted. 'Yes, I know. Why is that a problem? Are you worried that she won't pass?'

But Fitz was already shaking his head. 'It's not that. It's just, well, I don't like it.'

'You don't like it.' May repeated, beginning to comprehend what was going on here.

Fitz nodded. 'They're treated her like a criminal,' he burst out, his tone laced with anger and indignation. 'She just wants the best for SHIELD. And they're treating her like- like-' He searched around for the right word. 'Like she's the enemy.'

May almost smiled. It was sweet, really. Fitz had always been a romantic, ever since May had met him as a kid on the Bus. But he still had a lot to learn about women.

'It's okay to feel that way, Fitz.'

Fitz looked up at May in surprise. May, of all people, was talking about feelings?!

'But you have to understand,' May went on. 'As much as you care about her, you have to respect her decisions. She took that promotion with eyes wide open. And you may not like it, but it does come with strings attached. She knows that.'

Fitz nodded slowly. May had a point, but that didn't mean he had to like it.

'And,' May added. 'Have you told her why you don't like it?'

Fitz thought about this. He hadn't, he realised slowly. He had gone on and on about how bureaucracy was destroying SHIELD, how polygraph are unreliable and invasive, how this security colour wheel thing is a total farce, but he hadn't actually told her why he was so worked up about the polygraph. It was because of her, always her, because he wanted to protect her from being treated like a criminal, because she wouldn't let him protect her from being treated like a criminal. Jemma probably thought he was just trying to control her, or be irritable for no reason.

May could see the gears turn in Fitz's head. She saw the moment of realisation in his eyes, when he leapt up from his chair and announced, 'I have to talk to Jemma.' He made a beeline for the door, stopped only briefly to call out 'Class dismissed, thanks, May!'