Irene Adler appears only in "A Scandal in Bohemia". Her name is briefly mentioned in "A Case of Identity", "The Adventure of the Blue Carbuncle" and "His Last Bow". Additionally, in "The Five Orange Pips", Holmes says that he has been outwitted four times, thrice by a man and once by a woman, although the story of "The Five Orange Pips" is set in September 1887, before "A Scandal in Bohemia", which is set in March 1888.