There is no wasabi in it. What sits between the fish and the rice is mustard, mixed up from powder, and it is there because wasabi could not be had out here, or in the Ogasawaras further south, for most of the islands' history. Wasabi can be had now. The mustard has stayed anyway.

The fish is sliced thin and given a short soak in a soy-based marinade, which turns pale flesh a translucent amber. This is Hachijojima, two hundred and eighty kilometres south of the city it belongs to. The rice underneath is sweeter than mainland sushi rice, sugared on purpose. Sweet rice, marinated fish, a smear of hot mustard: the balance is nothing like a Tokyo counter, although Tokyo is technically where you are standing.

Whatever came up that day goes onto it. Marlin, mahi-mahi, grunt, amberjack, butterfish, sea bream of several kinds, alfonsino, tuna, bonito, flying fish. Read the list through and you have a rough inventory of the water around Hachijojima.

Marinating, sweetening, substituting — every element here is a solution to something not arriving by boat. The boats are reliable now. The solutions have outlived the problem, which is usually how a local food turns into a local food.