She tells Joan that she can never tell anyone about what she saw because it would put all of their lives in danger.
Corbett went back into his house and told Joan about the water.
"But he told Joan he knew where there was a hidden treasure."
He told Joan he went to the castle himself.
She threatened Allen with the switch if he ever told Joan.
They told Joan about what they had seen that morning on the island.
They told Joan what they had discovered in the clearing that morning.
Meanwhile, Jim has decided to tell Joan who he is.
Afterward he went to tell Joan what he had done, and met the doctor on the stairway.
A glance at the envelope told Joan that it had been posted nine days ago.