Unlike the other specials, this story is set in an alternate 19th‑century Japan called The Grand Jipangu, an alternate version of the Grand Line. The special is divided into two parts: in the first, Buggy the Clown causes trouble in the town where Detective Luffy is stationed; in the second, a mysterious girl named Vivi appears. Several minor characters from the main series make cameo appearances. The Oyabun specials continued with five more installments following this one, many of which were Christmas and New Year specials, with occasional fillers.