Bob said,'So what's the Doctor after?'  Peri shrugged.  'Oh, come on.  He told you, I know he did.  I know he did'

'No, really,' said Peri.  'If I knew, I'd tell you.  You'd probably have a better chance of understanding it than me'

Bob's apartment was small and spartan.  Other than a few tidy bookshelves - Peri was sure the books were alphabetised - and another shelf for record albums, there wasn't much in the place.  A single Dali print hung over the sofa.  She couldn't see a TV anywhere.  The kitchen was pristine, but Peri suspected that Bob never cooked.

You would have thought Bob's study would be just as much a disaster area as his office at work.  You'd have been wrong.  It was squeaky-clean - he even dusted behind the computer with a cloth before he sat down and switched it on.  A home-made shelf over the desk held a row of computer manuals lined up like soldiers.  They were alphabetised, Peri saw.  Another shelf held a row of books on the occult.  A mandala postcard hung from the bottom of the shelf by a yellowing square of Scotch tape.

Bob said, 'I wonder what it is... a satellite-based laser?'

'A stolen space shuttle computer.'

'A suitcase-sized nuclear bomb!'

'Whatever it is,' said Peri, 'it must be something pretty major for him to just vanish like that.'

'And stay vanished,' said Bob.  'I don't remember the Doctor being so paranoid.  He was more likely to charge in and make a bunch of noise.  He didn't care what anybody thought.'

'Maybe it's not just him.  Maybe there's somebody with him that he's got to protect.'

'Maybe he's in jail,' said Bob.  'Sneaking into the guard's offices to borrow the phone.'  Peri had to smile.

Bob logged on to check his electronic mail while Peri flipped through a computer magazine.  It was full of circuit diagrams and listings of programs, excited ads for a dozen brands of home computer, and pictures of barbarians rescuing damsels.  She couldn't find anything about the new network Bob seemed to find so exciting.

'Why is the net such a big deal, anyway?  It's just a bunch of scientists and generals sending each other computer messages, isn't it?  Why don't they just phone one another up?'

'One day you'll be able to order a pizza over the net,' said Bob, his back to her.  'It won't just be businesses that have modems.'

'You've got one'

'If they knew I had one, the telco would charge me business rates.  But one day soon, owning a modem will be just as normal as owning a phone.  This year some people did their Christmas shopping online.  You don't just get information from computers now, you interact with other people.  Email and Usenet are going to completely change the way human beings communicate.'  Bob was getting so enthusiastic he was actually looking at her.  'The written word is far more precise than speech.  Imagine conversation without the mumbling, the false starts, the half-chewed ideas.  Imagine a world of people talking in sentences that they've actually thought about first.  The net is gonna change how we think.'

Peri was impressed. 'Is that what it's really like online?'