D minor - The German marking "Schattenhaft" means Shadowy. Flowing but not too fast.
There is an undercurrent of night about the spooky third movement; while "Scherzo" means "joke", this movement is remarkably spooky and even grim. If the first "Nachtmusik" possessed a friendly mood disguised in grotesqueries, this movement is a demon sneering at the listener. Nonetheless, as the Spanish musicologist José L. Pérez de Arteaga points out, this movement is really "a most morbid and sarcastic mockery of the Viennese waltz".
The movement begins with a strange gesture: a pianissimo dialogue between timpani and pizzicato basses and cellos with sardonic interjections from the winds. After some buildup, the orchestra sets off on a threatening waltz, complete with unearthly woodwind shrieks and ghostly shimmerings from the basses, with a recurring "lamenting" theme in the woodwinds.
The scherzo is contrasted by a warmer trio in the major mode, introduced by and containing a "shrieking" motif beginning in the oboes and descending through the orchestra.
The brilliance of this movement lies in its extroardinary and original orchestration, which gives this movement a strongly nightmarish quality. Multiple viola solos rise above the texture, and there is a persistent timpani-pizzicato motif that pervades the dance. The theme and its accompaniment are both passed around the orchestra rather than being played by a specific instrument. At one memorable point in the score, the strings are instructed to play pizzicato with the volume fffff, with the footnote, pluck so hard that the strings hit the wood.
"Le Cauchemar" (The Nightmare) by John Henry Fuseli. This painting illustrates the sinister mood that pervades this scherzo.