Aunt Inheritance arrives at Swift House and announces it is time for the Swift family reunion.

Aunt Schadenfreude settles family disputes and tells the assembled relatives she will name her successor in three days.

Candour asks Schadenfreude to bless his engagement to Daisy DeMille; she publicly refuses and orders Daisy to leave.

Someone pushes Aunt Schadenfreude down the staircase and stages the scene to look like an accident.

Inheritance refuses to call the police and assigns Gumshoe Swift, a private detective, to handle the case.

Shenanigan, Phenomena, Felicity, and Erf form an investigative team and compile a list of suspects.

Overnight, someone steals the cars' steering wheels, cuts the phone line, and chains the estate's gates shut.

Gumshoe Swift is found dead in the library, his skull crushed beside a booby-trapped bookshelf.

Pamplemousse publicly challenges the hidden killer to a deadly game of Scrabble on the front lawn.

The anonymous archer wins the Scrabble duel and kills Pamplemousse with a crossbow bolt.

Cook announces that Aunt Schadenfreude has died from her injuries.

Shenanigan follows Daisy and Candour into the hedge maze; Candour knocks Daisy unconscious and holds Shenanigan at gunpoint.

Candour fills the house with laughing gas; Schadenfreude appears in the cellar and Candour is crushed by falling gravestones.

Aunt Schadenfreude is revealed to be alive, her ghostly pallor the result of a generous coating of flour.

Aunt Schadenfreude appoints Fauna as the new Swift family matriarch and removes her iron collar for the first time.

The Swift family reunion begins when Aunt Inheritance summons all living relatives to Swift House, where Aunt Schadenfreude announces she will choose her successor within three days. A killer's scheme is set in motion when Schadenfreude is pushed down the stairs after refusing to bless Candour's engagement, prompting Inheritance to appoint the hapless Gumshoe and lock down the estate. The children form their own investigative team as the killer strikes again, murdering Gumshoe in the library and Pamplemousse during a deadly Scrabble duel. Cook's announcement that Schadenfreude has died raises the stakes before Shenanigan unmasks Candour as the murderer in the hedge maze. A final confrontation in the cellar ends with Candour incapacitated by falling gravestones and Schadenfreude dramatically revealed to be alive. The crisis concludes with the appointment of Fauna as the new family matriarch, marking a hopeful new chapter for the Swifts.

The central mystery from reunion to resolution.

Shenanigan sneaks John the cat into Aunt Schadenfreude's coffin during the family's monthly funeral rehearsal.

Phenomena accidentally creates cyanide in her attic laboratory and stores it in a skull-marked bottle.

Shenanigan, Phenomena, and Felicity sneak into the cellar and locate Shenanigan's gravestone and its definition.

Shenanigan drops her gravestone on the cellar floor and deliberately breaks it in two.

Flora warns Shenanigan and Erf to keep their heads down and trust no one at the reunion.

Shenanigan overhears Daisy confessing to Flora that she has done something terrible and that Candour must not find out.

After Pamplemousse's death, the children recover the fatal crossbow bolt and find a brief note in the killer's handwriting.

The children discover the killer kicked John the cat to access the roof through Shenanigan's bedroom window.

Maelstrom and Inheritance bring the children into the hidden room and reveal the family's desperate financial situation.

The living Swifts use the EEK machine and contact a ghost who warns of danger, says the treasure is under the house, and tells them to ask the cat.

Someone burns the children's evidence, knocks Inheritance unconscious, sets the hidden room ablaze, and shoots Flora.

The assembled Swifts wrongly accuse Cook of being the murderer, refusing to accept her as part of the family.

Shenanigan leads Candour to the cellar and stalls for time by pointing out the gravestone carved for the house itself.

Daisy reveals that Candour charmed and robbed her, then threatened her family's reputation to force her into the marriage.

Shenanigan tears a page from the family dictionary and holds it to the light, revealing Cantrip Swift's hidden treasure map.

The story's foundations are laid before the reunion begins, as Shenanigan explores the manor's secrets, discovers her gravestone's damning definition, and defiantly breaks it in two. When guests arrive, Flora's warning foreshadows the danger ahead, while Shenanigan's eavesdropping on Daisy and Flora convinces her she has identified the wrong villain. The investigation deepens after Pamplemousse's murder as the children recover crucial evidence and piece together how the killer accessed the roof and disguised Gumshoe's true cause of death. The hidden room finally yields its secrets when the adults reveal the family's desperate finances and the ghost machine points toward the treasure's location beneath the house. A wave of violence destroys the children's evidence, injures Flora, and sends the family wrongly turning on Cook out of classist suspicion. The truth emerges in the denouement as Daisy exposes Candour's crimes and Shenanigan makes the first real discovery of Vile's Hoard in centuries.

Hidden rooms, hidden clues, and a hidden killer.

Shenanigan discovers a hidden room behind a large oil painting in a corridor but cannot get inside.

Shenanigan sees Aunt Inheritance slip into the hidden room behind the painting late at night.

Maelstrom urgently tells Shenanigan to keep the secret room hidden and show her house map to no one but him.

The children deduce the killer crushed Gumshoe's head with a statue to conceal two items removed from the library.

Shenanigan accidentally reveals the existence of the secret room to Phenomena and Felicity during their heated argument.

Fauna explains to Shenanigan that Felicity is mistreated by the family because of her unremarkable dictionary name.

Fauna tells Erf that no one in the world gets to decide their identity except themselves.

Shenanigan notices the handwriting on Schadenfreude's funeral place cards matches the note found on the crossbow bolt.

The three Swift sisters reconcile and apologize to one another after Aunt Schadenfreude's funeral.

Shenanigan stops Phenomena from drinking a beverage in the ransacked laboratory that has been laced with cyanide.

Shenanigan spots scratches left by John the cat on Candour's hand, confirming the doctor is the murderer.

Candour confesses at gunpoint that he forged Daisy's handwriting, planned to become patriarch, and killed to seize the treasure.

Schadenfreude strips Candour of the Swift name, excommunicates him from the family, and seizes all his assets.

Aunt Inheritance writes 'Erf' on a nametag and hugs her grandchild close, accepting their chosen name and identity.

Felicity publicly argues that Candour must face the police for his crimes, and Fauna orders the family to cooperate.

The story's key turning points begin early as Shenanigan discovers a hidden room and watches Aunt Inheritance enter it, while Maelstrom's suspicious secrecy suggests the adults are concealing something important about the house and the treasure. The investigation's most critical breakthrough comes when the children decode the true manner of Gumshoe's death, and Shenanigan's slip during a bitter argument forces the secret room into the open. A series of emotional revelations follows as Fauna helps Shenanigan understand Felicity's pain and empowers Erf to claim their own identity, while the sisters finally reconcile after their fierce quarrel. Clues converge as Shenanigan connects the place card handwriting to the killer's notes, then narrowly saves Phenomena from cyanide-laced liquid in their ransacked laboratory. The confrontation in the hedge maze and Candour's confession strip away the mystery and expose the full depth of his greed and ambition. Justice and change arrive together as Candour is excommunicated, Felicity's courage brings real law enforcement to the estate, and Aunt Inheritance's small act of writing three letters on a name tag signals a new era of acceptance for the Swifts.