“Here is the level 1 mechanical shed,” Mother said. “When the mine starts up again, your noncon will find you here, and we will all work again. I like to work.”

But the strange machine on her back deck would not dismount.

• * * *

The shuttle attack group now retreated downward, some dropping weapons and equipment in their haste. Their tunnel led to the elevator terminal underneath the city. The platform’s steel grating rang with boots. “Hurry!” shouted those on board. There was only enough time for one trip before the operation began.

“Where is Mother?” “There’s our Iron Lady!” “Uh-oh, she’s been boarded.” Some men stepped grimly off the elevator, weapons drawn.

“Stop!” Ishikawa called. “There’s no time for this. With her armor, she’ll be safe, barring a nuclear strike. Mother, take the rear-guard position. Now we have to go down.”

Mother turned around, directing her weapons up the tunnel. Somewhere beneath, a massive engine throbbed; the elevator platform sank from view.