FamousPsycho1960 · Bernard Herrmann
'The Murder' (the shower scene), bars 1–16: built one entry per bar from the top down in bars 1–8, then repeated with upward glissandos in bars 9–16
Not a chord in the usual sense but four neighbouring notes, E♭, E, F and G♭, spread out so each is a major seventh from the next. The strings enter one by one from the very top of their range downwards, then attack the notes again with sliding upward glissandos. Those spread-out half-step clashes, played loud without mutes, are the shrieking stabs of the shower scene.
Also called Shriek, the 'slashing' chords, The Murder cluster, Psycho Shower Cluster
Sources: Pearson Edexcel A-level set-work guide, Herrmann: Psycho · Royal Holloway Teacher Hub, 'Bernard Herrmann's Film Music: Psycho and others' · Bill Wrobel, 'Chord Profile #2 (Psycho)' (from the written score)