Grete loves Fritz, a young composer. Her father, old Graumann, a retired civil servant, fritters away the little the family has left to live on in the pub. Fritz wants to go out into the world in search of an »elusive sound«, and follow his artistic calling. He leaves Grete behind – he knows he'll only be ready for love when he's become an »artist by the Grace of God«. An old woman arrives, just as Fritz leaves, asking Grete ambiguous questions about her relationship to Fritz. The noise from the nearby pub, where her father's partying with his skittling brothers, gets louder and louder. Grete suggests to her mother that she could work as a servant, to better the family's circumstances. Her indignant mother, thinking this would jeopardise the family's honour, forbids it. Old Graumann and his drinking pals burst in: Dr. Vigelius, an actor, the landlord and guests and staff from the pub. The actor sings a courting song on the landlord's behalf – her father having gambled Grete away playing skittles. Grete, outraged, says that she's engaged to another man, which starts a furious family argument. Left on her own, Grete decides to run away. Finding herself by a lake in the woods, Grete decides to drown herself. Then the moon rises, and she's transformed by the magic of night. She passes out. The old woman appears again and admires the unconscious girl's beauty. When Grete comes to, the old woman persuades her to follow her. Act 2 Ten years later. Grete, now »Greta«, is the celebrated star of La casa di maschere, a demimonde establishment on an island in the gulf of Venice. Evening falls. The girls discuss Greta's relationship with a Count, who's trying to win her heart. But Greta's reluctant, the Count reminds her of Fritz. When the Count arrives he informs the Baron, another regular guest, about his plan to abduct Greta. When Greta finally appears the men flock around her. She seems in a melancholy mood and tells of a strange, recurring dream. Increasingly pestered by the men, she challenges them to a competition: with a night with her as the prize for the best story. The Count sings a strange ballad about a »glowing crown«; the Chevalier a cabaret song about the »flower girl of Sorrento«. Greta can't decide who should win. The Count urges her to flee with him, but Greta refuses. A boat comes ashore: a strange hunch brought Fritz to the island. He tells of his yearning for a mysterious sound and search for his childhood love, who he thinks he has found again at last. Greta awards him the prize for the loveliest story: a night of sensuous joy. It slowly dawns on Fritz that Grete is no longer the middle-class girl she was. When she explains that she's loved hundreds of men before him, he rebuffs her, accuses her of being a prostitute and leaves the island. Greta is now willing to follow the Count. Interval Act 3 Years later. Dr. Vigelius and the actor are sitting in a theatre bar, discussing a new opera being performed that evening: »The Harp«, composed by Fritz. The two men reminisce about old Graumann and his daughter. A member of the chorus pops in. The second act's begun, a success seems guaranteed. A policeman helps Grete inside. She was in the performance. The music moved her so much that she suddenly felt weak. A »dubious individual« accosts her: She's the »Tini« he spent the night with – Grete, deserted by the Count after a few years, now earns a living as a common hooker. The other guests are horrified and want her thrown out. Dr. Vigelius recognises her and stands by her. He feels partly to blame for her fate because he egged old Graumann on to gamble his daughter away. The audience leave the theatre: the end of the opera scandalised them, the evening's a flop. When Grete hears that the composer's ill, she's overcome by the desire to see Fritz again. Marked by illness, tired and disappointed, Fritz listens in amazement to the dawn chorus, which seems more insistent than ever before. His friend Rudolf arrives and tells him about the intendant's offer to give him another chance, and compose a new ending. But Fritz feels too weak. He asks after a woman, he thought might have been Grete. When Rudolf tells him it was just a »common prostitute«, Fritz realises the enormity of his guilt. He now knows why his work mangaged to convey misery and longing, but not happiness. Rudolf promises to bring Grete to him. Left alone, Fritz hears the mysterious »distant sound« again. Dr. Vigelius arrives and tells Fritz about Grete's misfortune. Grete appears. Fritz understands at last that love, art and nature are one and the same thing. With Grete Fritz thinks he possesses the »distant sound« once and for all. He feels strong enough to rewrite the end of his opera. Grete hopes to find peace with him at last, but he dies in her arms.