Irrene cam sex
Even though Irene does not want money or power for the pictures, Sherlock is tasked in getting them back.
She is using them, and other information on her mobile phone, for her "protection".
She is brought to Sherlock's attention when he and John are summoned to Buckingham Palace by Mycroft and are asked to take on a case of national importance.
Irene had taken compromising images of a young female member of the British Royal family during a dominatrix session.
Irene Adler is manipulative, devious, enigmatic, and clever enough to even give Sherlock Holmes a run for his money.
Whilst Mycroft is telling Sherlock about Irene, he states that she is a dominatrix who gives out 'recreational scolding' to people.She has been in the middle of two political scandals in recent years, one of them involving a famous author, in which she had an affair with both sides.