Presenting a rebuttal to editorials opposing the nuclear arms freeze with Dr. Jack Geiger, Dr. George Kistiakowsky, Dr. Herbert (Peter) Schoville and Dr. Kosta Tsipis of MIT.

Evolution and the future of the human race are among topics in Carl Sagan's and Ann Druyan's book, "Shadows of Forgotten Ancestors: A Search for Who We Are." Included is an excerpt of the astronomer Harlow Shapley speaking at the beginning. Carl Sagan also reads an excerpt from the book at the end.