While Elsie might not be that far back, her story came out in November 2013, the idea was conceived several years before. Not just Elsie, but the entire PSI premise was an idea floating around in my head for years before Elsie's Secret was published.
The Institute for Psychic Studies - IPS - is ran inside an old, stone mansion on extensive grounds in a remote area of Minnesota. This is where professors, teachers and scientists work to find answers to the whys and wherefores of human psychic ability. This is also where Calea Fontaine (Gavin's Woman) works as a teacher and where Gabe Nicholetti (Blind Sight) was raised.
However, IPS is also a cover for a private, secret agency - the PSI - operating in tandem with the federal government. The PSI work in the background to defend and shield unwary victims against the twisted underside of a psychic society bent on exploiting an unsuspecting, mundane civilization.
Because Elsie was the first of the PSI stories, she has a soft spot in my heart. I hope you'll check her out, and the entire PSI world!
More info on Elsie: