Black Butler Sebastian and Ciel investigate a number of murders, prostitutes gruesomely murdered by a man they call Jack the Ripper. Ordered by the Queen of England, Ciel visits the Undertaker to view the body and retrieve information, but the undertaker has one request for his information, a funny joke. After everyone tries their luck at making the Undertaker laugh, Sebastian must succeed where the others have failed.
They believe the killer who is the Viscount of Druitt, Lord Aleister Chamber, will be at his Aunts next party, so in order to go Ciel must dress like a young woman and flirt with the suspect to possibly catch the killer in the act. But Elizabeth, Ciels fiancee is at the party too so Ciel must do everything in his power to avoid her so she does not recognize him and possibly tarnish the Phantomhive name if caught.