They were in a vast apartment on rue du Faubourg-Saint-Martin, less than ten minutes by foot from where the body had been found. On the topmost of seven floors, it boasted impressive headroom, its ceilings having been removed to expose sloping rafters and the underside of the building’s roof. This was what miserable garrets looked like once they had fallen into the hands of those with the means to transform them into bohemian chic.