"Three, two, one ..." Yamato says, and presses a few keys. "Go."

The alert he sets off is a small one -- one that could easily be a glitch, or something rustling just the right way, or a mouse. He's still acutely aware that there's only so many of those he can set off before the Commander realises what's happening.

He opens two security doors at the same time, one at the top of the stairs, and one at the bottom.