The story of the composition of Shostakovich's Fourth Symphony at the height of the Lady Macbeth affair (1935–6), its withdrawal at an advanced stage of rehearsal (avowedly because of the composer's dissatisfaction with the finale) and the subsequent proffering of the Fifth Symphony as “a Soviet artist's reply to just criticism“, is well known. But only since the recent re-emergence of the Fourth Symphony has it been possible to discover to what extent this work represents “the path not taken”, and to assess whether the jolt that his music suffered at this period was fundamentally beneficial, or harmful, or neither.