Irene Adler of "A Scandal in Bohemia" by Arthur Conan Doyle is one of the few people to outwit Sherlock Holmes. Not only is she a stunningly beautiful woman, sharing Holmes' love of music and herself being a talented singer, but she also shares with Holmes a complex and subtle intellect and a deep understanding of human behavior.
Holmes obviously admires Adler. When he asks the King for a photograph of her as payment for his services, one wonders about what sort of feelings Adler arouses in him. Although some subsequent readers have tried to infuse romance into the story, there is no suggestion of sexual desire in the actual narrative. Instead, Holmes seems mainly to keep the photograph as a reminder of his own fallibility; the evidence of his having been completely outwitted counteracts his tendency towards arrogance and intellectual pride.