Dan "The Da Vinci Code" Brown has just written a book about them, and now a court case in Belfast could unearth some of the most closely-guarded information about the one of the most-secret organizations in the world: the Freemasons.
The ultimate fraternity, the Freemasons have been around since the end of the 16th century, and rumors abound that some of the most-famous men in the world, from presidents to politicians, count themselves as members.
Even Brown, famous for "The Da Vinci Code," which stirred up huge controversy in the Catholic Church, felt the organization was worthy enough for a Robert Langdon (Tom Hanks) treatment.
Brown's latest book, "The Lost Symbol," set in Washington D.C, sees the book's protagonist get far more than he bargained for after accepting an invitation by a Mason to deliver a lecture.
A murder and a mystery ensue as the bad guy in the book threatens to make public a secret video of Washington's elite involved in Masonic rituals.
In an unusual twist, a court action in Belfast could be a case of art imitating life.
The way the Grand Lodge of Free and Accepted Masons or Ireland does its business could be made public in a court case that is brewing in Belfast.
The dispute stems from 2007 meetings of the Antrim lodge in its Belfast location being recorded and then sent to members.
Northern Ireland police were asked to look into the incident, but they could not ascertain if a crime was committed.
Though the Grand Lodge said it dealt with the affair internally, members Stewart and Brian Hood (father and son) are taking legal action over the incident.
"I can confirm that my father and I have laid the writ. We are happy to be Freemasons, but are appalled at the conduct of the management of the provincial lodge of Antrim," Brian Hood told the Belfast Telegraph.
"It is our intention to have a court hearing. If we cannot get a fair hearing and justice within the Masonic Order, then we have to seek justice elsewhere and take steps to have injustice addressed."
The Hoods have already served John Dunlop, the provincial grand master of Antrim and general secretary of the Masons in Ireland, and are about to serve Barry Lyons, the Dublin-based Grand Secretary of the Grand Lodge of Free and Accepted Masons of Ireland.