I wouldn't put it past him to run a secret society.

There's probably some kind of secret society behind all this.

"It was like some secret society that only a few people seemed to know about."

A society so secret we can't even explain what it is.

One might even use the word as code by members of a secret society.

This secret society killed people for political and religious reasons.

He was supposed to be the leader of a secret society.

And into conflict with a secret society, every member of which is supposed to be dead.

If the secret society is mentioned by name, they are expected to immediately leave the room.

About some other secret societies, a good deal more is known.