Clara Ormond is the second daughter of a wealthy family in Ireland. Her older sister Ursula is beautiful, but Clara has a stunning singing voice. Her father and Ursula forbid her from singing in the house, where Ursula’s suitors may hear and become enchanted by her. Clara goes for walks in the woods and sings.

One day, she encounters a carpenter working. She introduces herself, and when the carpenter barely responds, she haughtily asserts her socioeconomic position. He introduces himself as William Rathbone and explains that he’s building a magical box that rivals the sound of birdsong, using the bones of a dead bird to make it immortal.

Clara spends all her afternoons in the forest with William, and one day, William asks her to marry him after he completes a luthier apprenticeship in Dublin. He promises to return in five years with a reputable trade to support her, and Clara agrees. They kiss.

The years pass, and in 1817, Ursula gets engaged. Her fiancé hears Clara singing one day and asks their father to marry her instead. Enraged, Ursula pushes Clara into the river, knowing she can’t swim.

William returns from Dublin that same day and finds Clara drowning. He pulls her out of the water, but he’s too late to save her life. Clara dies in his arms. William catches her last breath in his handkerchief and tucks it into the case of his newly crafted violin, meant to be a gift for her. Clara’s consciousness transfers to the violin.

William plays the violin at Clara’s funeral, and the people there begin to question her death, leading to justice for Clara’s murder. William moves to Europe and can’t bring himself to play the violin again until he meets the “greatest maestro who ever lived” (86).

Gabrielle drives Walter and Devlin to meet an associate of Walter’s in Bath before dropping the violin off at a dendrochronologist in Bristol. Gabrielle plays classical music on her car stereo, and Devlin admires her passion for music. Walter brings up Devlin’s own musical past, but Devlin refuses to talk about it.

Devlin falls asleep, and when he wakes, Gabrielle and Walter are discussing the violin. Gabrielle couldn’t find a luthier’s stamp, but she did find a serial number. The dendrochronologist can tell the age of the wood, which will help. Gabrielle drops Devlin and Walter off at Larkfield Hall before she continues toward Bristol.

Walter tells Devlin that Margot Clement’s descendant, Lord Ravenshaw, lives at Larkfield Hall, and Walter plans to explain the story of the violin to him. They find Lord Ravenshaw shooting clay pigeons. He assumes that Walter and Devlin are reporters, and they play along. Ravenshaw explains that the violin was a gift to Margot from a Middle Eastern prince, but he no longer owns the violin, as Christie’s paid him the insurance money. Devlin and Walter leave with the violin, feeling defeated as their hope for a simple resolution dissipates.

Gabrielle arrives at the home of Roger, a former friend she studied music with. When Gabrielle began studying with Max Daunt, she and Roger became more competitive, but after Gabrielle’s injury, their friendship fizzled. Roger warmly greets Gabrielle and invites her inside.

Gabrielle explains how she obtained the violin and was able to play it. Roger asks Gabrielle if she still talks to Max, then apologizes. He explains his equipment to Gabrielle and that it might take time to date the violin’s wood. Gabrielle has booked a B&B, but Roger insists she stay with him and his family. She agrees and offers to cook dinner.

After a peaceful evening, Gabrielle can’t sleep. She makes a cup of tea and finds Roger awake and working. He tells her that the violin’s wood isn’t from the Musical Woods, the location in the Alps from which Stradivari sourced the wood for Stradivarius violins. The wood is from the 1800s, but it doesn’t match any of the wood that Roger has in his database.

Gabrielle shows Roger the headlines about the stolen violin, asking if he thinks it may be a match. Roger doesn’t think so, even though it has an identical body length. He suggests that Walter and Devlin go to Italy to find out more.

Walter and Devlin return to London. Devlin worries about what to do with the violin, but Walter prods him to talk about his breakup with Melissa. Devlin thinks the violin might’ve been a better choice than getting engaged to Melissa, and he and Walter return to London in peaceful silence.

Verity and her men break into Gabrielle’s apartment after tracing the violin from Devlin and Walter to her with the help of a hacker. Verity doesn’t find anything that helps her locate Gabrielle or the violin, so she heads to Oxford University to see Sofia Alves, an art history professor and formerly a shady art dealer.

Sofia taught Verity how to deal in stolen and forged art but has since given up her criminal past. Verity asks Sofia for help moving a piece of dubious origin and validity. Sofia refuses, but Verity blackmails her into selling it.

Gabrielle returns home from Bristol to find her shop and apartment burgled. She calls Walter and Devlin, and they finally tell her the truth about the violin. Gabrielle believes that by proving the violin’s true provenance, they can get the thieves off their backs.

Devlin takes the violin, and Walter and Devlin apologize for involving Gabrielle in the increasingly dangerous situation. After they leave, Gabrielle cleans up her apartment and finds her cat Satie hiding. She doesn’t tell Walter and Devlin about the email she received from Verity.

William moves to London, still unable to play the violin that contains Clara’s consciousness. He takes a job as a luthier, making new violins. While delivering a violin, he runs into Niccolò Paganini in a luxury hotel, complaining. William has Clara’s violin with him, and Paganini asks William if he can play the violin. William refuses.

Paganini invites William to his rooms to discuss the violin, and William tells him the strange truth. He allows Paganini to play the violin. Paganini and the violin play beautifully together, and Clara loves the music she makes with him. Paganini writes “Bellezza Nascosta” about William and Clara, and the riposte spells their names. He asks to take the violin on tour, and William agrees, as long as he promises to bring her back.

Paganini tours with the violin, and he and Clara begin to understand each other. Clara realizes that Paganini plays for the sake of improving his skill, breaking apart musical norms, and reconstructing something new. They succeed together until Paganini dies, after making his son Achille promise to return the violin to William.

In 1841, Achille returns to London and finds William’s shop, but William died six months before. Clara hopes Achille will leave her at William’s grave, but he doesn’t.