The narrative of the piece, Danse macabre is based on an ancient legend, where Death appears at midnight every year on Halloween, summoning the dead from their graves to dance for him while he plays his fiddle. His skeletons dance until dawn breaks, when they must hide away again until the following year.
The piece opens with a harp playing a single note twelve times to represent the twelve strokes of midnight, followed by the solo violin's opening tritone (A and E flat) - an interval so dissonant that it was known as the diabolus in music (the Devil in music) during the Medieval and Baroque eras.
To achieve this on open strings, the E string of the solo violin must be tuned down a semitone to an E flat, in an example of scordatura tuning (Bach, one of Saint-Saens' great musical heroes, makes a similar demand of the cello in the fifth of his Cello Suites). The first, restless theme is heard on a solo flute, followed almost immediately by the second theme, a descending scale on the solo violin. The macabre element is emphasized further by the inclusion of the Diesirae Gregorian chant from the Latin Requiem Mass, but in A major rather than minor key, and in a playful manner rather than its usual solemn state. An energetic coda seems to lead the music to a conclusion, but is interrupted by a sudden pause: the cockerel's crow, played by the oboe, signifies the breaking of dawn and the skeletons scurrying back into their graves.