Section: Audition at the Opera
Granny Weatherwax and Nanny Ogg sit on a mountaintop, trying to be a coven of two and failing. Nanny mentions Magrat, now queen, and worries that Granny is losing herself to boredom and Borrowing. They need a third witch. Meanwhile, in Lancre, a young woman called Agnes Nitt - overweight, sensible, with an extraordinary singing voice - has secretly harboured an alter ego called Perdita and has left for Ankh-Morpork to audition at the Opera House. At the Opera, Agnes is astonished by the grand building and meets the eccentric doorkeeper and the nervous Walter Plinge. She auditions, demonstrating a voice of supernatural range and the ability to sing in harmony with herself. The selection committee, led by new owner Mr Seldom Bucket and musical director Salzella, is more interested in the pretty but talentless Christine. Agnes is assigned to the chorus while Christine gets the lead. Elsewhere, the Opera Ghost - a mysterious figure in a mask - has begun terrorising the company, leaving notes, dropping scenery, and, most recently, committing murder.
On page: Esmerelda Weatherwax, Nanny Ogg, Magrat Garlick, Agnes Nitt, Walter Plinge, Salzella, Seldom Bucket, Christine, Dr Undershaft, Mr Goatberger
Section: The Witches Arrive
Nanny Ogg and Granny Weatherwax travel to Ankh-Morpork, ostensibly because Nanny wants to check on the publication of her cookbook (The Joye of Snacks) but really to recruit Agnes Nitt as the third witch. They arrive at the Opera House, where the Ghost's reign of terror continues - more notes, more threats, and another death. Agnes discovers that she can throw her voice with supernatural precision, making it seem as though Christine is singing beautifully when Agnes is actually providing the voice from the wings. The Perdita part of Agnes's personality is outraged by this arrangement but Agnes's desire to be liked overrides her pride. Granny Weatherwax infiltrates the Opera as a cleaner and begins investigating the Ghost, recognising that something more complex than a simple haunting is occurring. Salzella, the sardonic musical director, manages the company's growing panic with weary cynicism.
On page: Esmerelda Weatherwax, Nanny Ogg, Agnes Nitt, Death, Walter Plinge, Salzella, Seldom Bucket, Christine, André, Tommy Cripps, Mr Pounder, Dr Undershaft
Section: The Falling Chandelier
The Ghost escalates his campaign, dropping a massive chandelier during a performance. Agnes saves Christine by pushing her out of the way. The Ghost begins communicating with Agnes directly, drawn to her extraordinary voice. He calls himself the Opera Ghost and occupies a hidden network of rooms and passages beneath the Opera House. Agnes is torn between fear and sympathy - the Ghost seems genuinely passionate about opera and music, but his methods are increasingly violent. Granny and Nanny explore the Opera's cellars and discover the Ghost's lair, a surprisingly well-appointed underground apartment. Granny begins to suspect that there are two people involved in the hauntings. Mr Bucket despairs as the company threatens to quit and audiences dwindle. Nanny Ogg discovers that her cookbook has been published with all proceeds going to the publisher, and she is owed nothing.
On page: Nanny Ogg, Agnes Nitt, Esmerelda Weatherwax, Greebo, Walter Plinge, Mrs Plinge, Salzella, Seldom Bucket, Christine, André, Enrico Basilica, Dame Timpany, Mr Goatberger
Section: Walter in the Cellars
Agnes is taken to the Ghost's underground lair and discovers his true identity - he is Walter Plinge, the simple-seeming odd-job man of the Opera House. Walter has a split personality: by day he is a shambling, nervous figure who speaks in a stammer, but as the Ghost he becomes confident, articulate and dangerously obsessive about opera. His mask conceals not physical deformity but the emotional transformation between his two selves. Agnes's Perdita personality recognises a kindred spirit - someone else divided between who they are and who they want to be. Meanwhile, Granny Weatherwax deduces that the actual murders are being committed by someone else entirely, using the Ghost as a cover. She confronts Salzella, who has been killing people and blaming the Ghost to drive down the Opera House's value so he can buy it cheaply.
On page: Esmerelda Weatherwax, Agnes Nitt, Nanny Ogg, Greebo, Nobby Nobbs, Detritus, Walter Plinge, Mrs Plinge, Salzella, Seldom Bucket, Christine, André, Enrico Basilica, Dame Timpany
Section: Salzella Unmasked
The climax takes place during a grand performance. Salzella makes his final move, attempting to kill Walter and frame the Ghost for the murders. Granny Weatherwax intervenes, using headology to expose Salzella to the entire audience. Salzella, cornered, attempts to fight his way out but is stopped by Greebo (transformed into human form) and the combined efforts of the opera company. Walter is revealed as the Ghost but treated with sympathy rather than punishment - his love of opera is genuine, even if his methods were extreme. Agnes decides to return to Lancre and take her place as the third witch in the coven, recognising that her two-in-one personality - sensible Agnes and dramatic Perdita - makes her ideally suited to witchcraft. Nanny Ogg negotiates a proper royalties deal for her cookbook. Christine continues to receive credit for Agnes's singing, which Agnes accepts with rueful grace.
On page: Esmerelda Weatherwax, Nanny Ogg, Agnes Nitt, Greebo, Nobby Nobbs, Detritus, The Librarian, Walter Plinge, Mrs Plinge, Salzella, Seldom Bucket, Christine, André, Enrico Basilica