Then Mrs. Whatsit explains that they are going to a foggy planet to see a medium. When they arrive Mrs. Whatsit, Mrs. Who and Mrs. Which intoduce the kids to the happy medium. After that the happy medium show the kids their home planet. The medium was so reluctant to show them something, but the kids get a vision of the dark thing surrounding the earth. Next Mrs. Whatsit explains that almost all the famous people in the world have been fighting the dark thing. Impatient, Meg asks about her father, Mrs. Which informs her that he is held captive on a planet the dark thing has taken over.