Detectives Guild was born out of a long tradition of Christmas treasure hunts for our daughter.
Each Christmas, and later birthdays as well, one of the presents would be hidden behind a trail of riddles that would take her all through the house finding hidden clues. The clues would eventually lead to the present hidden somewhere in the house.
Later, these riddle chains led not only through the house, but through town, requiring her to interact with store clerks to give code phrases to receive the next clue.
Detectives Guild started as a way to give other kids that same sort of experience electronically, but has evolved to be far more than that. Fairly quickly it grew to support Choose Your Own Adventure sorts of mysteries along with the more standard riddle and puzzle solving type, along with expanding the mysteries to ones suitable for adults, too.
The only limit now is our authors' creativity!