This film records a lecture given to students by outspoken nuclear critic, Dr. Helen Caldicott, president of Physicians for Social Responsibility in the United States. Her message is clear: disarmament cannot be postponed. Archival film footage of the bombing of Hiroshima and images of its survivors seven months after the attack heighten the urgency of her message: namely, that unless we shake off our indifference and work to prevent nuclear war, we stand a slim chance of surviving the 20th century.