Harper, in turn, cocked her head to study him. “The first sighting of such a creature was, I believe, recorded in 1555 by Olaus Magnus, the archbishop-in-exile of Uppsala, Sweden,” she murmured thoughtfully. “The occasional reappearance of its kind in northern waters over the next two centuries has led some modern commentators to speculate that they were the prototype of Iormungand, the serpent of Midgard, who encircles the world, and whom Thor might have landed with an oxhead for bait were it not for the cowardice of the giant Hymir.”

“Don’t tell me, let me guess: it’s really, like, a big roll of toilet paper or something.” And with a derisive snort, he moved away towards the giant pig of Chalfont St. Giles.

Harper frowned sternly. “A ribbon worm,” she said, screwing the point of her stick into the earthen floor. “Phylum Nemetinea. And quite rare at this size, actually. Smuggled in from Osaka, where it washed ashore on New Year’s Day, 1995. Many Japanese believe that their appearances serve as predictors of earthquake … The spike secretes poisonous mucus,” she called, in an attempt to hold his interest, but he had already rambled off under the flambeau.

They were in the Secret Museum, a network of medieval vaults beneath a street of warehouses in Southwark. Forgotten, presumed destroyed, the catacombs had been appropriated by a small group of connoisseurs for the display of their bizarreries. Beneath the low stone arches of the underground corridors, jars, aquaria, display cases and picture frames stood on top of pedestals, rested on tables, leaned against derelict sarcophagi, or hung upon the walls. They were lit only by fire—by torches guttering here and there in iron cressets, filling the place with oily smoke. This was an admittedly melodramatic touch, but some of the less scholarly visitors seemed to enjoy it.

As Storm continued away down the corridor, Jorge Swade, the museum’s curator and sole cicerone, found himself caught uncomfortably between his most cherished patron and the man he presumed to be her beau. His bloodshot eyes blinked furiously, his buck teeth chattered like a dentist’s toy, but he didn’t know what to say to ease the tension. He settled for making ridiculous and servile bows in both their directions. Which made his lank hair brush the shoulders of his red sports jacket, leaving an oily stain.

As for Harper, she went on frowning at the retreating Storm for a few moments more. Of all the curios in the place, she really found him the most curious of all. Clearly, he was besotted with the girl—clearly enough to pinch her own antique heart with a twinge or two of jealousy. Why the pretense of indifference then? Why did he insist on it?

With a determined tug at the brim of her Borsalino, with a firmer grip on the dragon head of her stick, she waddled after him now, under the torch, down the corridor, brushing past the cringing Swade.