Professor Owl, who rushes to the schoolhouse full of his fine feathered students as a drum roll, is played on a snare. A brief musical section introduces "the subject for today": the study of musical instruments. Professor Owl explains to the class (and the viewer) that all music originates from four core sounds: toot (
brass), whistle (
woodwind), plunk (
strings) and boom (
percussion).
Toot The film jumps to a group of four
cavemen, each of whom have discovered the nuclear form of one of the above sounds. A portly Caveman Toot discovered that blowing through an old cow's horn produces a pleasing "toot". The short advances to ancient
Egypt in 2000 BC, where Caveman Toot discovers that metal horns produce even better sounds. He celebrates by breaking into a two-note
jazz solo as Egyptian characters painted on the walls boogie down. Professor Owl explains that making a trumpet longer made its tone lower. The scene switches to a
Roman trumpeter who crashes into a column and bends his horn into a grotesque shape, but soon discovers that despite this change in form, the trumpet does not sound any different: it is possible to change the horn's shape without changing the pitch. However, as Professor Owl explains, this horn can only produce certain notes; in order to get all of the notes required for even a simple tune, they would need four horns of different lengths. If there is a horn with valves, then the valves control the passage of air, and this fact is celebrated with another solo.
Whistle Caveman Whistle is trying to impress his "cave girl" by blowing through a tube of grass; he further discovers that adding holes to the tube allows him to modify the "whistle" in interesting ways—the more holes Whistle adds the longer the grass tube gets and he invents the first flute. The cave girl is impressed, but then a rival caveman appears, bonks the cave girl on the head with his club, and drags her off by the hair—which makes Caveman Whistle angry. Professor Owl explains that this system of holes is the basis for every woodwind instrument, including the
clarinet played by
Johann Sebastian Bach and the
saxophone played by a jazz musician.
Plunk Caveman Plunk has discovered that plucking on the string of his bow produces a pleasant "plunk" sound. An off-screen choir explains–as the animation shows–how to create a simple harp from "taller" Caveman Plunk's bow by adding a jar to make a
resonator, adding some extra strings, changing the jar to a box of wood, sliding it down and adding tuning pegs, and rearranging it all. Plunk invents the first harp. Professor Owl mentions that the musician can either
pluck the harp, which is played by a taller Caveman Plunk, or play it with a
bow, which is played by a shorter Caveman Plunk. The short briefly visits several periods in history, where there are several stringed instruments being played in similar fashion, and finishes with a
string quartet, and all of them ending with the strings being broken.
Boom Caveman Boom hits his stomach to produce a "boom", and hits other things with his hand and his club to make other sounds. Professor Owl explains how a variety of percussion instruments emerged from this basic theory, ranging from rattles to complex drum kits and even the bass drums of marching bands.
Conclusion The chorus recaps that all music, from the
trombone to the
calliope to the
banjo to
Latin percussion to "music oriental" to an
orchestra in a concert hall, emerge from the four core sounds with Caveman Toot in the brass section, Caveman Whistle in the woodwind section, Caveman Plunk in the string section and Caveman Boom in the percussion section, all wearing
top hats. ==Cast==