Berg was obsessed with symmetry in his works and Lulu is no exception, the whole being perceived as a palindrome or mirror.
Lulu's popularity in the first act is mirrored by the squalor she lives in during act 3, and this is emphasised by Lulu's husbands in act 1 being played by the same singers as her clients in act 3.
The motifs associated with each, being repeated.

This mirror-like structure is further emphasised by the film interlude at act 2 at the very centre of the work.
The events shown in the film are a miniature version of the mirror structure of the opera as a whole (Lulu enters prison and then leaves again) and the music accompanying the film is an exact palindrome – it reads the same forwards as backwards.
The centre-point of this palindrome is indicated by an arpeggio played on the piano, first rising, then falling (shown here on the top staff).

Berg assigns specific vocal styles to each character with descriptive orchestral representation, recapitulative episodes to emphasise psychological significance and pitch-sets.
Recapitulation includes having single singers performing multiple roles.
The use of pitch includes the use of twelve-tone rows.
Berg was obsessed with symmetry in his works and Lulu is no exception, the whole being perceived as a palindrome or mirror. Lulu's popularity in the first act is mirrored by the squalor she lives in during act 3, and this is emphasised by Lulu's husbands in act 1 being played by the same singers as her clients in act 3. The motifs associated with each, being repeated.
This mirror-like structure is further emphasised by the film interlude at act 2 at the very centre of the work. The events shown in the film are a miniature version of the mirror structure of the opera as a whole (Lulu enters prison and then leaves again) and the music accompanying the film is an exact palindrome – it reads the same forwards as backwards. The centre-point of this palindrome is indicated by an arpeggio played on the piano, first rising, then falling (shown here on the top staff).
Berg assigns specific vocal styles to each character with descriptive orchestral representation, recapitulative episodes to emphasise psychological significance and pitch-sets. Recapitulation includes having single singers performing multiple roles. The use of pitch includes the use of twelve-tone rows.
Lulu (opera)