The children looked up at him.

‘Zoo books,’ said one.

‘Yes,’ he replied, taking the sketchbooks away from their grubby hands and closing them.

‘Why have you got zoo books?’

‘I make zoo books,’ he said.

They thought about this. Their simple grasp of professional careers did not reach so far. One nudged the other.

‘Are you going to put the beast in your zoo books?’ the nudged one asked.

‘The beast?’ he asked. ‘Which beast?’

‘The hill beast. It has teeth.’

‘Great large teeth.’

‘It eats men up.’

‘And swine.’

‘And swine. With its great large teeth. It has no eyes.’

‘Come away!’ their mother called, and the two children scurried back down the aisle to her.

Drusher looked around the cabin. It was just as he had last seen it. The agri-worker continued to snooze; the old woman was still reading. The only change was the twins, who now sat facing one another, like a mirror.

The cabin door thumped open and flakes of sleet billowed in around several newcomers. A black-robed demograph servitor, its face a cluster of slack tubes beneath augmetic compound eyes. A short-haired woman in a leather bodyglove and fur coat, carrying a brown paper parcel. Another agri-worker, his face chilblained, fighting to keep his long-haired terrier from snapping at the roaming hound. A matronly progenium school teacher in a long grey dress. The short-haired woman helped the matron with her luggage.

‘Leofrik! This is Leofrik!’ the servitor called as he walked the cabin. ‘Present your papers!’

Each voyager offered up his or her documents for the servitor to scan. Gershom was very particular about its indigents, the side effect of being so close to a warzone. The Departmento Demographicae maintained a vigilant watch on the planet’s human traffic.

The servitor, waste spittle drooling from its mouth tubes, took a long time studying Drusher’s papers.

‘Magos biologis?’

‘Yes.’

‘Reason for travel?’

‘I went through all this at the terminal this morning.’

‘Reason for travel?’

Drusher sighed. ‘Seven years ago, I was commissioned by the Lord Governor of Gershom to draw up a comprehensive taxonomy of the planet’s fauna. It is all but complete. However, a curiosity has appeared in Outer Udar and I am travelling there to examine it.’

Drusher wanted to go on, to talk about the extended deadlines he had been forced to request, the increasingly reluctant project funding that had obliged him to take the overland coach instead of a chartered flier, the preposterous idea that he might have missed an apex predator.

The demograph servitor wasn’t interested. It handed the papers back to Drusher and stalked away.

In the meantime, the short-haired woman had taken the seat opposite him. She smiled at Drusher. Her face was lean and sturdy, with a tiny scar zagging up from the left-hand corner of her lip. Her eyes were dazzling amber, like photoluminescent cells.

Drusher looked away.

‘Magos biologis?’ she said.

‘Yes.’

‘I couldn’t help overhearing.’

‘Apparently.’