I sat on the toilet seat. Ben was in the bath, telling me a long story about what had happened in school that day. ‘Fatima said I shouldn’t be on top table for Maths so I asked her what seven and seven was and she said seventy-seven and I said don’t be silly that’s wrong and she said she was only joking so I said what’s the real answer then and she said she knew but she wasn’t going to say so I said it’s fourteen actually and she said she knew that all along and then she went round telling everyone I didn’t know what seven and seven was and I was just telling her off for saying fibs about me and then Miss told me off for talking and that wasn’t fair because she told me off but not Fatima and said if I kept talking I’d have to be moved off the top Maths table away from all my friends and Fatima’s not even my friend!’

‘Yeah, that’s terrible.’ He’s always going on about this Fatima girl. I think they fancy each other a bit, that’s why they’re always winding each other up.

‘If they take me off the top Maths table it’s not fair. Then Fatima will laugh at me. She’s already on the top Literacy table and I’m not.’

‘Listen, Ben, keep still. I’m gonna nitcomb you in a special way today.’

‘What you gonna do?’

I hesitated a bit. I hadn’t been planning to tell him, but now I thought if I didn’t he’d wonder where I’d disappeared to and call out for Mum and Dad. Also he might scratch his head and squash me.

‘Listen, Ben, don’t be alarmed—’

‘Like an alarm clock?’

‘Yeah, don’t be alarmed like an alarm clock. I’m gonna go tiny and go in your hair and hunt those nits down.’

Now, of course I didn’t need to do this. I could have just wished the nits would vanish. But I wanted to make an adventure out of it. A quest. Otherwise, I thought, life would get too boring if you never had to actually do anything. OK, the ant-killing hadn’t been as much fun as I’d expected. But this was different. Those nits had been driving Ben mad for years. They deserved their comeuppance. And I was going to be the one to give it to them.

Ben looked at me in a kind of solemn way. ‘That’s impossible.’

‘I know it is.’

‘If it’s impossible you can’t do it.’

‘Yes I can, because I’m magic.’

‘If you’re magic, turn into a helicopter.’

‘I’ll get you a helicopter, if you just sit still and don’t scratch your head, all right?’

‘What colour helicopter?’

‘Any colour.’