The second movement follows immediately. Its structure is one of continuous development by thematic metamorphosis, with the introduction of new and contrasting material at two points. The movement could, very loosely, be described as being in the form A-B-A'-C-A"-coda. However, the steady metamorphosis of the initial theme means that it is never actually repeated: only the atmosphere of the theme is present. The theme itself, on solo cor anglais, is first cousin to the flute theme which opens Debussy’s Gigues. Indeed, Brian's approach to structure in this movement is similar to that of Debussy’s: growth from within, by continuous thematic development and metamorphosis. Other composers such as Strauss and Schoenberg also used this approach, and no doubt influenced him in this respect, though Brian’s orchestral textures are in a different world from those of any of these.
The theme is repeated on oboe, accompanied by a doleful chromatic counterpoint on second oboe, two cors anglais, two clarinets, two bass clarinets and muted cellos and violas divisi, an extraordinary and haunting sound.  The atmosphere of this theme never leaves the music, though it is never heard again in the same form. Sometimes the intervals are changed; sometimes only the rhythm remains: sometimes even this is distorted. The theme appears in many guises: as a canon at varied intervals from bar 301; as a powerful melody in the 'cellos from bar 320, and, greatly transformed, in the string accompaniment from bar 335. It makes its final appearance, fragmented but still recognizable, in the disintegration which occurs from bar 420 to the end of the movement; and its elements are present in the final valediction in the strings.

There are many original strokes in this movement, both thematic, harmonic and textural. One example is the interruption of the steady progress of the metamorphosis of the first theme, at bar 295, by a heavy-footed processional on upper woodwind, stopped horns and timpani in what is clearly a foretaste of the mood of the funeral march that forms the finale. This is swept away after only two bars, but it has made its ominous mark, like the sudden appearance and disappearance of a spectre. The first main episode breaks in at bar 314. It is a violent chromatic outburst, with thick chords in parallel movement marked "Sempre Pesante Possib[i]le (Each note hard and heavy)".