She has a fine track record of bringing wildly idiosyncratic music to the masses but this is impenetrable even by Björk’s wilful standards. The song is a caustic barrage of thundering IDM rhythms, topped off with the Icelander’s trademark, tremulous wail. Not unlike much of her previous material, then, but it lacks the undercurrent of vulnerability and petrified melody that characterises a great Björk record.