minute or so, as if he was having trouble thinking.

"You were lucky, getting this far."

"Yeah," we said, "We sweet-talked the old man at the gate."

"That's my Dad," said Brain, "He likes to know everything that goes on round the house."

We shivered a bit, inside.

"What about at night. Can he see people in the dark too?"

"Oh sure," said Brain, "Infra-red, and heat-sensing cameras everywhere. No trouble. Nothing gets even close to the house without my Dad spotting it!"

We wondered how much Brain's Dad knew about our little visit a few weeks ago. He'd probably watched us going round the house! That wasn't a pleasant thought!

"What's the smell?"

"Medicine." said Brain.

"No, not that smell. It's all through the house."

"Oh that. Its just something My Dad likes doing. He's keen on making things. He's always tinkering with machinery and oil and things."

"What does he make?"

"Not allowed to tell," said Brain.

"Robots?"

We shouldn't have said it. As soon as the word came out Brain stared at us in a way we'd never seen before. He looked frightened and worried and scared all at the same time. He drew his legs in tighter.

"How did you know?" he asked, "Did Dad tell you something?"

"No," we said, "Just curious."

"Well don't ask! What goes on in this house is none of your business!"

"OK!" we said, " Don't get angry! We were just asking!"

"How much do you know?"

"Nothing. Honest."