‘Great. Have you always operated in such an unorthodox manner?’

‘Also essentially classified, but for the sake of this discussion, yes.’

‘Would it kill you to tell me more about this?’

‘Yes.’

‘I didn’t mean literally,’ said Drusher.

‘I did,’ said Eisenhorn.

‘Do you find that people who meet you end up regarding you as an arrogant son of a bitch?’ snapped Drusher.

Eisenhorn stopped. He did not look around.

‘I mean, come now, sir,’ said Drusher. ‘I’m trying to assist. Could you ease off with this hard-nosed act?’

‘It’s not an act, magos.’

‘Terra’s sake,’ Drusher sneered. ‘Did someone once hurt you really, really badly?’

Eisenhorn slowly turned around to look at Drusher.

Drusher took a step back.

‘The list of people in this galaxy who have not hurt me is very, very short, magos,’ he said.

Drusher adjusted his spectacles, pursed his lips and nodded.

‘You’ve asked some questions,’ said Eisenhorn. ‘My turn. What is the average bite radius of Ursa minora gershomi?’

‘Twelve centimetres.’

‘Majora?’

‘A range up to seventeen,’ said Drusher. ‘Nineteen for the arctic form. The cave ursid–’

‘Is an ultra-rare, prehistoric form,’ said Eisenhorn. ‘It has probably been extinct for some centuries. If it exists at all, it is restricted to the northernmost area of Outer Udar.’

‘Oh, it exists,’ said Drusher. ‘Or, at least, it did thirty years ago. I have examples and evidence in my taxonomy. And you’re wrong about its locale. There were still some in the Tartred Mountains.’

‘Are there any other apex predators on this planet whose kills would resemble those of the banded or grey ursids?’

‘Not to an expert. You can’t rule out introduced exotics, of course.’

‘You’ve seen that here?’

‘More than once. Marshal Macks will corroborate that.’

‘Why do you want to leave Gershom?’ asked Eisenhorn.

The question took Drusher aback slightly.

‘My… my work is complete,’ he replied. ‘It has been for years. A complete taxonomy. It’s simply a case that there is nothing left to be done. But, unfortunately, economic circumstances prevent–’

‘You could have retired,’ said Eisenhorn. ‘I hear that’s nice.’

‘I… sort of had, sir. Forced to by circumstances. I had a property down on the Bone Coast and – ahmm – worked with maritime ornithological efforts.’

‘You kept birds in a cage in a shack on the beach, magos,’ said Eisenhorn. ‘Your retirement was enforced, by your own admission. If you had been able to leave Gershom, at any point in the last three decades, you would have done so.’

‘Yes.’

‘Because, somewhere, there were still things to be done, things to be found, secrets to be learned?’

‘Yes.’

‘So it’s fair to say that you would not have retired, given the choice, because there is still so much work to be done?’

‘I suppose so,’ said Drusher.

‘Work that you really want to do, and which you would prefer not to leave in the hands of others to finish?’