In a way, I was glad when a drunkard started shouting obscenities from the audience. Up on the podium, Captain Malang Lar kept talking, and then someone from the chamber of commerce stood up and tried to shout down the drunk man, but by then it was too late. Constables in pillbox hats and flashing blue epaulettes came bursting through the audience from the back of the room and started wrestling the drunkard away from the proceedings. But he was determined to put up a fight, brawling with the constables and staggering into a table, sending it toppling.

Paladin swivelled around. ‘Disturbance detected,’ it kept saying. ‘Disturbance detected.’

Father started rolling up his sleeves. ‘I suppose I’d better . . .’ he was saying, making a show of letting everyone know he was at least considering getting involved, even though he was happier behind a desk than wrestling with drunks.

Then we both realised that Adrana had slipped away from the table.

‘Find her!’ Father snapped at Paladin.

The robot swivelled its head and rolled away from the table, picking a path through the brawl. Someone gave Paladin a kick, just for the fun of kicking a sentient machine. Paladin was used to that sort of thing. It wobbled a lot, but managed to stay upright.

‘It should have kept a better eye on her,’ Father said, fuming as he tugged his sleeves back down again.

‘Paladin can’t help it,’ I said. ‘It’s just an old robot trying its best. Look, I’ll go and see if I can find her. They were only letting people in through the north entrance, weren’t they?’

‘No,’ Father said, wiping a hand across a sweat-glistened brow. ‘They were using both entrances, and you can bet your sister’s headed for one of them.’

Paladin was still sweeping the room, its dome spinning around, lights flashing agitatedly behind the glass.

‘All right,’ I said. ‘You go back to the cloakroom, where we came in. I’ll go to the south entrance.’

‘Can I trust you to come back?’ Father asked.

‘Of course.’

I meant it, too. I had no intention of disobeying him. I wanted all of us to get back on the tram and ride along Jauncery Road to the house, away from the drunken chaos that had started out as a polite civic function. I wanted to be back in my room on the third floor, next to the parlour with all our books and maps and games.

‘Then be quick about it,’ Father said.

I left the table, skirting around the brawl – which was quietening down now, as more constables arrived – and began to make my way along the length of the Hall of History.

A clammy cold hand closed on my wrist.

‘That sister of yours is a disruptive influence. The sooner she’s out of your life, the better. Shall we look for her together?’