In the next two minutes, my friend demonstrated an elegant agility. Over, under, at one point limboing nearly horizontal, she was a lithe wonder.

Drio could have been a very lucky man.

When she reached the fuse box on the far side, Ms. Clara and I cheered. Leo wrenched on the switch.

It didn't move.

She threw her shoulder into it, grunting with exertion. The lasers flickered and died.

The three of us froze, straining to hear any far-off alarm, but ...