The program opens with a film visit to the National Institutes of Health labs in Bethesda, MD. Dr. Tomlinson explains the life cycle of schistosomes via snails to humans. Dr. Wright describes the characteristics of the disease and shows films of victims of the parasite. He also explains how U.S. troops fighting in the South Pacific could bathe in infested streams and bring the parasite to the U.S. unless they use chemical repellants on their clothing and body. Dr. Cram describes her team's search for a U.S. snail that could serve as a host for schistosomiasis. The NIH schistosomiasis snail study collection from around the world is displayed. Dr. Nolan describes her search for a safe chemical compound to pour into waterways to kill snails on a large scale, and she demonstrates how it works.

The workings of an atomic bomb are explained through atomic reactions and fusion. Comparisons are made to TNT and hydrogen explosions, and some peaceful applications for nuclear energy are discussed.

This program defines biological warfare, its basis being what has happened experimentally with animals and accidentally with people, such as the Q fever epidemic. Dr. Langmuir, from the Communicable Disease Center in Atlanta, describes how an attack might contaminate air with infectious material or water supplies with contaminants spread throughout the distribution center. He also enumerates the agencies and organizations included in the public health safety net. Norman Kiefer of the Federal Civil Defense Administration suggests that we need better sampling and lab methods, vaccines, and investigation procedures to combat communicable diseases. The viewers were urged not to spread rumors but rather to request the pamphlet "What You Should Know About Biological Warfare."

Using diagrams, Dr. Lowell J. Reed first describes the history of epidemics, the origins of disease, using measles and small pox as examples, and means of transmission. He then demonstrates the epidemic theory where St is the number of people susceptible to the disease over time multiplied by 1 minus qct (the probability of a person with the disease meeting a susceptible person) equals C t+1(cases over time). Also factored into this equation is the number of people who develop an immunity to the disease after recovering from it. The theory is then tested against experience. Dr. Reed sets up an experiment demonstrating the practical application of the theory using a model. He then discusses epidemic control focusing on isolation of people who already have the disease, and immunization of people who are susceptible to the disease.

Two seemingly unrelated crimes are linked and subsequently solved through forensic techniques involving spectrometry, blood typing, and ballistics with the use of microscopic methods.

Lynn Poole discusses the work of an industrial hygienist and notes that although there are many aspects of industrial hygiene, this program focuses on atmospheric contamination and its remediation. Dr. Anna M. Baetjer describes dusts (especially silica dust) and solvents (especially carbon tetrachloride) and the research being done to determine their effect on human workers. Charles E. Couchman, a Baltimore city industrial hygienist, demonstrates how carbon monoxide testing can be done with an instrument. Hopcalyte, developed at Johns Hopkins University and University of California, is used to reduce carbon monoxide levels. Allen D. Brandt, an engineer for Bethlehem Steel, shows photographs of exhaust systems at local industries and the collection and removal of particulate matter.

The program begins with a tour of the Children's Hospital School of Baltimore, Maryland. Dr. Raymond Lenhard describes the symptoms of poliomyelitis, or infantile paralysis, and treatment of the disease. In the exercise room, a physical therapist demonstrates the muscle test for fingers and shoulders and how patients progress from simple to complex exercises. Patients are shown in crutches and leg braces, in the rocking bed, and in the treatment pool doing underwater exercises. "Iron lung" respirators are demonstrated and explained. Lynn Poole interviews two patients who recovered from polio, and he alludes to research being done in polio immunization.

Volcanoes are found in certain areas of the earth that are also susceptible to earthquakes. Pressure beneath the crust of the earth forces lava and hot rocks up through the crater of volcanoes. Various types of lava and volcanic rocks are discussed.

Research in human engineering affects many operations of everyday life. Experimentation with sizes and shapes of numbers, knobs, and traffic signs can make driving safer and machines easier to operate. The first eight or nine minutes are missing from the videorecording of this program.

Fossils of prehistoric organisms show the characteristics of ice age life and the earth's geologic past.