Not Your Company Man - First Contact

When the moon first starts to slide in front of the sun during an eclipse, it's barely visible. Just the faintest, tiniest mark to begin - if you weren't looking for it, you'd hardly know it had happened. This is what is known as first contact. From that point on, the moon's progress is constant, becoming more and more obvious, until the inevitable blackout of the sky.

The headache doesn't go away until Noah gets home. Or what currently passes for home, anyway - it's been so long that he's almost starting to think that it is.

He's got no idea what it is that caused it; probably nothing more than a momentary blip. In the end, he decides it's nothing to worry about.
A blip, indeed, the smallest possible change to him overall. In the Nexus, something small's almost more improbable than something large. Fitting, given the source of the change.

Sometimes, it's little changes that cause big effects.
Can't get much smaller than a few genes changing. Important genes, but still.
(The truly improbable thing lies in that same change taking place throughout a human body... but is it so much more so than what he'd seen?)

He just pours himself a coffee and relaxes, knowing nothing of it at all.