Set in the town of Apronwood, the story of Ivy Shambitt and the Sound Machine begins with a chorus of Apronwood folk telling a story from the town’s history. They sing of Mr and Mrs Shambitt and their extraordinary infant daughter, Ivy who, although blind, has an amazing gift of sound. This causes quite a stir for the wives of Apronwood whose husbands demand talented children of their own. Being unable to provide the husbands with their own talented young, the wives of the town decide that the next best thing is to do away with Ivy’s parents and to remove Ivy’s gift by amputating her tongue and abandoning the girl down near the creek.
Little Ivy survives but it is ten years on that the heart of the story really begins to unfold.
Pippa Van Hoozer, a bespectacled social outcast is on the run from the school bullies; Patience Primrose (the leader of the popular girls group), Prudence Pinch and Penelope Freckle. She’s given the girls and the boys from the neighbouring town head lice and now the girls can’t see them anymore. To teach Pippa a lesson, the girls decide it will be fun to smash egg yolks into her hair (the ultimate head lice cure!). After a rather obvious game of hide and seek, there is a struggle and the girls, tease and torment her and just before Patience cracks the egg over Pippa’s head they hear a frightful roar bellow out from the distance. Frightened, the girls run off, vowing to finish what they started with Pippa later. Pippa tries to run off too but has hurt her ankle in the struggle and as the noise perseveres a young girl appears. She is dirty and smelly looking, holding a glass in one hand and in the other its lid. The noise hits its crescendo, the filthy girl seals the jar and suddenly the noise stops. She edges toward Pippa, who is frozen in terror and makes a bandage for her ankle. After her initial fright Pippa gets over her fear and misgivings and discovers that the girl’s name is Ivy Shambitt; she has no sight and no tongue but has an amazing gift of sound and has used it to tell Pippa her name. Even more astonishingly, she has used this talent to create the roaring that was just heard. She captures sound, and is able to manipulate it any way she wants and she has many more jars of sound at her home near the creek. Pippa decides that Ivy will be her new best friend and leads Ivy away talking of the fun they will have together.
Meanwhile in the centre of the town, Eloise Primrose, Elisia Pinch and Estella Freckle (Patience, Prudence and Penelope’s mothers) are preparing for the annual Apronwood Auxiliary Tea Party. The women are fed up; the Tea Party isn’t bringing in crowds like it used to and the town’s name is deminished in reputation and their husbands have also abandoned them. Talk turns to the Ivy Shambitt incident bringing the town bad luck, but Eloise soon puts a stop to that before one of the newest members of the town, Ernestine (Pippa’s mother) can hear what went on so long ago. Like her daughter she too seems to be an outcast as the group of women berate her and her daughter but she endures the snide comments and manages to keep her kind demeanour with the ladies. She desperately tries to fit in, even baking for the Tea Party bake-off. In the distance Ivy’s sound erupts, startling the ladies enough to move them inside. All leave except Ernestine who sees someone coming out of the darkness. It’s Pippa and Ivy follows not far behind. Pippa begs her mother to let her “keep” Ivy and she is taken in by the Van Hoozer family.
Later that night, Eloise, who is picking nits from Patience hair has a thought and dials Elisia’s number, who is also picking nits out of Prudence’s hair. Eloise hatches a plot to bring the tourists back to Apronwood. They will need an attraction worthy of bringing in the crowds; a mythical, mysterious beast and the sound she heard this past night has given her the idea. They will make up sightings and dress Patience in a beastly costume and the town will have its own legend. With that a plan is devised and put into action.
Much, much later that night Pippa is crawling around her bedroom with an open jar. It seems Ivy is trying to teach Pippa some of her tricks. Ivy is gobsmacked by her surroundings; the Van Hoozer’s house is certainly different from her home at the garbage drop by the creek, filled with unusual sounds she is overwhelmed by. Pippa’s father, Englebert enters the room explaining to Pippa, Ivy belongs with her family and they will try and find them for her but is interrupted by Ernestine. She is distraught; she can’t seem to bake anything worthy of the Tea Party bake-off. She is determined to show up the women of the town but, dejected, she has resigned herself to cooking a slice of toast. To take her mind of things she asks the girls what they’ve been doing, to which Pippa replies they are catching sounds - or trying to. Ivy feels her way to towards a light bulb in the middle of the room and holds a jar up to it before sealing the jar. She runs her fingers over the jar, shakes it, opens the jar again and a hum of electricity escapes. But that’s not all; Ivy shakes the jar vibrantly with her hand over the top and the sound that escapes is astounding to Englebert and Ernestine; it is so many different sights and sounds to them all at once. Even more interesting than that Mr and Mrs Van Hoozer can taste the most delicious watermelon coming out of the sound and once the jar is closed again they snap out of what appeared to be a delirious trance. This gives Ernestine an idea; they’ll make a sound cake for the bake-Off on Saturday and give the reigning champions, the Primroses, a run for their money.
It’s Saturday and Apronwood’s annual Tea Party has begun and the whole town is in attendance. While there are mountains of cakes lined up on numerous table Ivy and the Van Hoozers stand behind a glass jar. As the judge, Eloise makes her way towards them, tasting and spitting pieces of cake out into a bucket held by Elisia. She arrives at the jar and proceeds to mock the Van Hoozers but they manage to persuade her to open the jar and the buzz of cicada escapes. They tell Eloise to shake up the jar and suddenly a full melody is heard and everyone seems to be under a ravenous spell. Not only can they hear the sound, the taste of it is ecstasy to them. The jar is closed and the spell is broken. As Ernestine explains that Ivy has made the sound cake and the town has just seen, heard and tasted her sound, a beast enters, hungry, heaving with breath. Eloise explains it is just her daughter, that the beast is going to attract tourists once again, but Patience enters soon after in what looks like a poor version of the one opposite her. Eloise has been so distracted by what has just happened she has no idea a real beast does in fact exists. The beast lunges towards the Tea Party and everyone panics but Ivy calms the beast with a sound from her jar. It turns to Ivy; with arms outstretched and hugs itself into her. Pippa grabs the jar, shakes it and a high pitched sound comes out that paralyses the beast and, scared, it runs away towards the creek. Ivy seems distressed by this and is trying to communicate with Pippa to no avail. While everyone is in a state of panic Eloise sees this as an opportunity; Apronwood now has two main attractions, 'a beast and a beauty'. As she voices her new found ideas, Pippa interjects and introduces Ivy Shambitt to the rest of the town. Eloise reacts only for a moment before sending the girls a glance as if to warn them off saying anything to tie them to the mystery of Ivy’s past. She makes a deal with the Van Hoozers, who have appointed themselves as Ivy’s legal guardians: build a device, one that will bring the monster out of hiding and devise a sound that can kill it. Tickets will be sold and out-of-towners can come and watch the killing of the beast. With the promise of money too great to resist the Van Hoozers make the deal with Eloise and the 'performance' will be called Ivy Shambitt and the sound machine.
As Ivy sweated and laboured over her creation, the sound machine, people of the town brought by bits and pieces for her to add to it. They also wanted to use her talents for their own personal gain. Eloise realised she could eat sound and never gain a pound, Estella wanted the voice of a tall dark, handsome stranger to keep her company and Prudence and Elisia got Ivy to cure their webbed feet. Everything came at a cost and the Van Hoozers were more than willing to exploit Ivy and her talents to make more and more money. Pippa, Ernestine and Englebert were becoming very rich. At the end of a long day Ernestine counted up the money they had made and entrusted Pippa with giving Ivy her “cut” of it. Pippa walks up to a tired and exhausted Ivy who collapses with fatigue, she is about to give the money to Ivy thinking it will inspire her to stay awake and finish her job. Instead she decides to keep the money and give Ivy her glasses instead and feeling guilty, leaves Ivy to slave away while she goes to bed. Ivy reaches for the hammer to continue construction but cannot find it. She feels for it but instead finds a furry paw belonging to the beast. Strangely Ivy is calm and so is the creature. They are in fact brother and sister. The beast is Ivy’s twin brother who was born with an imperfection all of his own. He had an extra tongue and an extra set of eyes and after Ivy’s murder the boy had been neglected; his hair began to grow and his teeth began to rot, making him look like the beast he was now. But Ivy knows this beast and strokes and pats him, studying him with her nose, it seems they have previously met.
The day of the Ivy Shambitt and the sound machine performance has arrived, audience members are being seated and a huge mass is on a stage covered by a drop sheet. Eloise welcomes everyone and proceeds to tell a made up version of the tale of the beast and introduces Ivy and her amazing talents. Ivy reveals the machine but Estella interrupts the show, stumbling onto the stage and, guilt stricken, begins to tell the story of long ago. They thought they had killed Ivy Shambitt until she showed up once again ten years later. Eloise and Elisia struggle to quiet Estella when Patience, Prudence and Penelope show up with a box filled with pieces of glass; they’ve smashed all of Ivy’s jars of sound. Pippa enters running, she tried to stop the girls but failed and goes to comfort Ivy but she pulls away. Eloise finally reclaims the stage and begins to encourage the audience to make sound. A roar of voices, bellow out and Ivy’s face begins to twist into fear. Pippa tries to quieten them but is unsuccessful. Ivy turns on her sound machine and reaches for a pair of headphones and puts them on. A hush comes over the crowd, the audience is dumbstruck. Pipa begins to realise she should never have bought Ivy into her town. Ivy motions for them to all look under their seats. They find blindfolds and put them on including Pippa who is blindfolded by Ivy. Ivy hits a switch on the sound machine and a luminous white light glows from the centre of the machine. Ivy works her magic and suddenly a gentle sound of wind is heard but it soon grows into a ferocious gale. The smell of rotting, putrid decay invades the space and smoke billows from the centre of the machine. Everyone is overcome, yelling, pleading, and threatening. A thud accompanies the wind, morphing into a loud boom, followed by an axe grinding and a cat hissing. Pippa apologises to Ivy for everything as a beast roars. The sounds build into a closing loud, magnified moment as it slowly begins to kill the townspeople; there are final screams before silence. Everyone around Ivy is dead.
A chorus begins to tell of Ivy and her beast destroying the town of Apronwood with her sound machine and sitting down to feast. It seems Ivy and her brother enjoyed the taste of human flesh. The poor women of Apronwood thought their husbands had left them but Ivy and her brother beast had feasted on them long ago. When the town ran out of husbands the next best treat was little girls and women. One person survived this ordeal, a doctor. He struck a deal with Ivy and her brother and transplanted the beast’s extra eyes and tongue to his sister and then swiftly fled. Now Ivy can speak and talk and it is she who gets the last word in as she bites at the last bit of flesh on a bone, stroking the beast who purrs like a kitten. She urges people to listen, for when someone is silent they can truly hear and like her when something is out of sight, it is out of mind. With that she laughs and the sound bends and magnifies and flickers away as it lights up the space into a rainbow of colour before quickly fading into darkness.