Gingerly, O’Singh stepped up to the doorway and ventured a foot inside. A small, wiry man stood at the window in shirt-sleeves, hands planted in his pockets; on his face a look of intense disappointment even before he turned to settle his cold gaze on O’Singh. A face like that of a greyhound with an obsession over what it must be to taste rabbit after it gets to catch one in its very last race.

‘I cannot tell you how exhilarated I am,’ gushed O’Singh. ‘I am here, really here, in the hallowed offices of the Investigations of the Para-Usual.’

Dr Pratt condescended to look O’Singh over with narrow, burning, scrutinising eyes. His heavy salt-and-pepper, tight-curled beard all but concealed lips that were working slowly, lending the effect of a beard bulging and squirming like a ferret seen through the opening of a bag or a trouser leg. Generally, it might be said, Dr Pratt’s was a face of misfortune. He had once injured himself badly in a night class. Night classes are usually non-perilous affairs. But Dr Pratt had chosen his in mountaineering.