Lynn Poole shows photos and demonstrations from past programs and poses questions for viewers on the topics of skin grafting, atoms, electroencephalography, x-rays, and diffraction grating. Afterwards he gives the answers with explanations. Next a series of six simple experiments are performed, questions are asked about each, and answers are given afterwards. The experiments' concepts include molecular model identification, cold steam power, surface tension disruption, carbon dioxide production, and interaction of acetone with acetate rayon.

Lynn Poole describes a diffraction grating as having ridged scales, like a butterfly's wings, that create iridescence. The 75,000 precise ridges must be so accurately spaced that it requires a special machine to make a diffraction grating. Dr. Henry H. Rowland developed the first one in 1860, but Dr. John Strong refined this machine, the ruling engine, in 1950. Using a model of the machine, Dr. Strong explains the operation of a ruling engine, focusing on the perfect twin screws that are its vital parts. The maker of these screws, David Broadhead, of Wellsville, NY, demonstrates how one cuts one of these screws on a machine lathe. In a film, Wilbur Perry, one of the most accomplished mechanical and optical technicians in making diffraction gratings, constructs parts of the ruling engine, including the diamond used to cut the 75,000 grooves on the aluminum-coated glass. Diffraction grating is the basis of spectroscopy, separating light into various colors for analysis.

Great scientists and their research are discussed including: Elmer V. McCollum and his discovery of vitamins A, D, and B1; John Boswell Whitehead and his work on dielectrics; Alexander Graham Christie's work on power plant design; the philosophy of George Boas applying the world of ancient Greece to modern thought; archaeology in the Near East by William Foxwell Albright; and Robert Williams Wood and his research into diffraction gratings and infrared filters. There is also a discussion of operations research and its applications in the American military effort.