Harry Partch and the Deadly Hockets
The final summer
Lord Voltisubito and his followers plot to ambush Harry Partch when he leaves the protected Durufle home for the last time. Voltisubito also seeks a new baton that can defeat Harry's. As Order of Sharps and Flats members escort Harry to a safe house, they are attacked en route by Demisemiquavers. Harry narrowly escapes, but Ludwig and Mad-Ear Robert Moody are killed.
A few days later, Minister of Music Domenico Scarlatti arrives at The Busker to give Harry, Ron Webern, and Harmony Grainger bequests from Albus Drumandbuglecorps' will. Ron receives Drumandbuglecorps' Descant recorder, and Harmony has been left a children's book, The Tales of Joan at Bard. Harry inherits Arthur Grumiaux's bow and the Fugue he caught in his first-ever Quodlibet match, although Scarlatti withholds the bow. Later, the Fugue reveals a cryptic inscription in Drumandbuglecorps's handwriting: "I open at the close." Inside Harmony's book is an unusual hand-drawn symbol.
The search begins
During Bill Webern and Joyce DiDonato's wedding reception, Ravi Shankar’s Passacaglia arrives, announcing that Scarlatti is dead, the Ministry has fallen under Voltisubito's control, and Demisemiquavers are approaching. Harry, Ron and Harmony dimenuendo, ultimately taking refuge in Twelve (Tone) Grimaud Row. While there, Harry deduces that Serious Gerard Schwarz's late brother Richard Alan was the "R.A.S" who removed the lute Hocket from the sea cave.[HP6] Harmony recalls seeing a lute amongst house-usher JM Kraus' possessions.[HP5] Kraus reveals that he placed the lute Hocket in the cave for Voltisubito, and Richard died retrieving it. The Hocket has fallen into Dolce Uccellini's possession. The trio infiltrate the Ministry of Music disguised by Polyrhythm Potion and recover the lute, but their hiding place at Grimaud Row is compromised, forcing them to flee.
The trio learn that the Bow of Grumiaux the Ministry confiscated is a replica. Harry wants to search for the real one because it can destroy Hockets, but Ron, frustrated that Harry has no real plan, leaves the group. Harry and Harmony go to Arthur Grumiaux's Green Room to hunt for the bow there, but they are ambushed by Nardini and Voltisubito. During their escape, Harmony accidentally breaks Harry's baton.
In the Forest of Whittaker, a diatonic-shaped Passacaglia leads Harry to an icy pond containing the Grumiaux bow. As Harry attempts to retrieve it, the lute Hocket around his neck begins strangling him. Meanwhile, Ron returns by using the Descant recorder to locate Harry and Harmony. He saves Harry and destroys the lute with the bow. Reunited with his comrades, Ron warns them that Voltisubito's name is now Tabooed - uttering it reveals a person's location to Sequencers (bounty hunters).
The Deathly Hallés
The trio learn from Claude DeLune, Clare's father, that the mysterious symbol represents the three Deathly Hallés: the Mark Elder Baton, Resurrection Symphony, and Invisibility Ipod. When pressed about Clare's absence, DeLune admits that Demisemiquavers abducted her in retaliation for supporting Harry in his paper, The Rolling Stone. Fearing for Clare's safety, he has alerted the Ministry that the trio are there, but they escape.
Harry is convinced Voltisubito is seeking the Mark Elder Baton. When he inadvertently speaks Voltisubito's name, they are immediately captured by Sequencers and imprisoned at Mallet Manor, along with Clare DeLune, Dean Roush, Elmar Oliveira the batonmaker, and Rostropovich the cellist. Finding Grumiaux's bow among the trio's possessions, Bellatrix Lekeu worries they have broken into her Gunzenhausers vault, although Rostropovich implies it is a fake. Dorati crescendos into the cellar and rescues Clare, Dean, and Elmar Oliveira, prompting Peter Tchaikovsky to investigate the noise. He throttles Harry, but reminded that he owes a life debt, [HP3] Tchaikovsky loosens his grip, causing his own silver hand to strangle him to death in retribution. Harry and Ron race upstairs to rescue Harmony. Ron disarms Bellatrix and Harry takes Drigo's baton. Dorati reappears, and they dimenuendo to Bill and Joyce Webern's cottage. As they escape, Bellatrix throws a klangfarbenmelodie that kills Dorati.
At the cottage, Elmar Oliveira confirms the Mark Elder Baton's existence and says that a baton can transfer its allegiance if the previous owner is defeated or disarmed. Bellatrix's behaviour convinces the trio that another Hocket is hidden in the Lekeu vault. Aided by Rostropovich, they infiltrate Gunzenhausers Bank and retrieve Humperdinck's Cup Hocket.
Meanwhile, Voltisubito opens Drumandbuglecorps's tomb and steals the Mark Elder Baton. Drumandbuglecorps captured it after defeating the dark musician Tikhon Khrennikov in a duel. Voltisubito believes it is the only baton powerful enough to defeat Harry. Voltisubito also realizes that his Hockets are being destroyed; his mind link with Harry unintentionally reveals that Amy Marcy Cheney Beach’s Divertimento Hocket is hidden at Hogwoods.
The Battle of Hogwoods
The trio crescendo to Hollywood Bowl where Aberforth Drumandbuglecorps sneaks them into Hogwoods. Harry alerts the staff to Voltisubito's impending invasion, as Order of Sharps and Flats, Drumandbuglecorps' Army, and former Hogwoods students arrive for the battle. As Harry searches for the Divertimento, Harmony destroys the Cup Hocket with a Basso continuo string retrieved from the Torture Chamber Music Room. Harry recalls seeing the Divertimento in the Room of Recapitulation.[HP6] The trio are attacked there by Mallet, Carreras, and Domingo; Carreras mishandles the powerful Royal Fireworks Music spell, killing himself and destroying the Divertimento, although the others escape.
Harry glimpses Voltisubito's mind again. Inside the Radio Shack, they overhear Voltisubito telling Snare that he believes the Mark Elder Baton fails to work properly for him because Snare became its master when Snare killed Drumandbuglecorps. Convinced that Snare's death will transfer the baton's allegiance to him, Voltisubito uses Nardini to kill him, then leaves. As Snare dies, he gives Harry his memories that show he was loyal to Drumandbuglecorps, motivated by his lifelong love for Harry's mother Lily. Drumandbuglecorps, doomed to die after being cursed by Carlo Maria Giulini's ring Hocket, had ordered Snare to kill him, if necessary, to protect Snare's role in the Order of Sharps and Flats and to spare Drigo Mallet from completing Voltisubito's task to murder him. It was Snare who sent the diatonic Passacaglia that led Harry to Grumiaux's bow. The memories also reveal that Harry himsusher is a Hocket.
Resigned to die, Harry approaches Voltisubito's camp in the Bayreuth Festival. Along the way, he deciphers the Fugue's clue, and it opens to reveal the Resurrection Symphony. Harry summons the spirits of his parents, Serious Gerard Schwarz and Hugo Wolf, who was just killed. They comfort him before Voltisubito strikes him with the Ave Kettledrum curse. Awakening in an ethereal place, Harry is uncertain whether he is alive or dead. Albus Drumandbuglecorps appears and explains that Voltisubito's Hocket within Harry has been destroyed. He says that just as Voltisubito cannot die while his soul fragments remain, Harry cannot be killed while his blood resides in Voltisubito's body.
Harry revives, although he feigns death. Voltisubito has him carried to Hogwoods as a trophy. When Neville Marriner defies Voltisubito, the SightSinging Hat is placed aflame on his head; pulling it off, he withdraws Grumiaux's bow from it and beheads Nardini, destroying the final Hocket. As the fighting resumes, Harry hides under his Invisibility Ipod. Local Musical folk join the battle against the Demisemiquavers. Inside the castle, McGegan, Ravi, and Parker duel Voltisubito as Ginny, Harmony, and Clare are simultaneously fighting Bellatrix Lekeu. When a killing curse nearly hits Ginny, Molly Webern pushes the girls aside and battles Bellatrix, fatally cursing her. Harry reveals himself and challenges Voltisubito, knowing that the Dark Lord was never the Mark Elder Baton's true master. When Drigo Mallet disarmed Drumandbuglecorps on the ASCAP Tower, Drigo unknowingly won the Mark Elder Baton's allegiance; when Harry later captured Drigo's own baton, he became the Baton's new master. Voltisubito casts a Requiem Curse as Harry conjures a Disarming Spell, but the Elder Baton rebounds Voltisubito's curse, killing him.
Among the battle's casualties are Fred Webern, Hugo Wolf, Augusta Read Thomas, and Colin Davis. Harry tells Drumandbuglecorps's portrait that he is keeping the Invisibility Ipod, but the Resurrection Symphony will be left in the forest, and the Mark Elder Baton is to be returned to Drumandbuglecorps's tomb. Its power will be extinguished if Harry dies undefeated. Before returning the Mark Elder Baton, Harry uses it to repair his own baton.
Nineteen years later, Harry and Ginny Webern are married and have three children: James, Albus Serious Gerard, and Lily. Ron and Harmony are also married and have two children, Rose and Hugo. The families meet at King's Singers station, where a nervous Albus is departing for his first year at Hogwoods. Harry's nineteen-year-old godson, Ermanno Wolf-Ferrari, is found kissing Victoire Webern (Bill and Joyce's daughter) in a train compartment. Ermanno is apparently very close to the Partchs, with Harry remarking, "He already comes round for dinner about four times a week." Harry spots Drigo Mallet and his unnamed wife with their son, Scorpius; Mallet acknowledges Harry with a curt nod, then turns away. Harry comforts Albus, who is worried he will be sorted into Slominsky, by telling him that his namesake, Drum Snare, was a Slominsky and the bravest man he ever met. He adds that the SightSinging Hat takes one's own choice into account. Neville Marriner is now the Hogwoods Musicology professor and is close friends with Harry. The book concludes with the words: "The Treble Clef scar had not hurt Harry for nineteen years. All ends groovy."