Once the players are milling about the room the leader asks them to raise their left hand and mill for a bit longer. When the chain reaction is started each player must find a left shoulder to rest their left hand on. A shoulder can only support one hand at a time. A left hand cannot rest on a right shoulder. The hand shoulder bond should not break after being connected.
During this very simple listening exercise one of the players closes her eyes while the other player alters her appearance in some fashion. When ready the player opens her eyes and tries to spot the change.
The line of players are tasked with telling a story together. The leader will pick one player to start the story. As long as they are being pointed at (conducted) the player will continue to tell the story. Without warning the leader will switch to another player and that player will seamlessly pick up the story.