Each half-hour episode focuses on a single subject in the field of natural science, such as the Solar System or the various functions of the human body. The information is presented in the "Eyewitness Museum", a computer-generated science museum. Various exhibits are shown, and stock video footage is usually seen through large windows or other depressions in the wall. The book series and the show share a striking visual style making notable use of the color white. During the newly produced content (as opposed to stock footage) a background is almost never used in favor of a stark white backdrop, presumably to make the presented object stand out better. In addition, almost every episode features a "Hero". The Hero is a character or object which drives the action of the show and is continually referred back to. These include the weather-vane chicken from Weather, the claymation baby Tyrannosaurus from Dinosaur, the paper boat from Pond and River, and the robotic Human mime artist from Human Machine.