In September 1827, Hector Berlioz attended a performance of Hamlet in Paris and became fixated on the Irish actress playing Ophelia, Harriet Smithson. He bombarded her with letters for three years and never received a reply. This episode examines how that unrequited obsession became the Symphonie Fantastique, a five-movement instrumental drama in which a despairing artist overdoses on opium and hallucinates his way from a ballroom to the guillotine to a witches’ sabbath. We explore the idée fixe, the recurring melody named after a contemporary medical term for obsessive preoccupation, and how Berlioz mutated it across the work to chart his own deteriorating state of mind.

We break down the orchestral innovations that scandalized 1830 Paris: two harps in the ballroom waltz, four timpani players imitating distant thunder, strings struck with the wood of the bow to mimic rattling skeletons, and the ophicleide blasting the Dies Irae funeral chant. We also follow the strange aftermath, in which Berlioz staged a revised performance in 1832 to ensure Harriet was in the audience, met her shortly afterward, and married her in 1833. The conversation closes with the polarized critical reception, Robert Schumann’s defense of the work’s hidden symmetry, and how the Dies Irae became a horror shorthand still heard in film scores today.

• How the romantic era’s cult of overpowering passion shaped Berlioz’s behavior
• Why writing five movements was different from Beethoven’s five-movement Pastoral
• The printed program notes Berlioz handed out and later tried to walk back in 1855
• March to the Scaffold and the plucked strings depicting a severed head
• The open question of whether a masterpiece justifies the obsession that fueled it