It will require two people who know this game to be in the secret. One of them leaves the room while his confederate remains inside with the others. He hides an article which the rest of the players have selected, in an adjoining room which is totally dark, placing a watch with a moderately loud tick, either on, or as near to the hidden object as he can. The rest of the players must not know anything about the watch, as they are kept guessing how the player who is out, succeeds in finding the hidden article in the dark room.

When everything is ready, the one outside is called in, led into the dark room, and hunts for the object. The rest must remain very quiet, as it breaks the "charm," so the leader says. Guided by the ticking of the watch, and knowing that it is there, he soon discovers the hidden object to the surprise of the others.

He and his confederate may take turns going out and after a while, if the company are very quiet, one of them might hear the watch ticking and the trick is disclosed.