Simon Light vient à l'Agence de détective Layton pour demander l'aide du Professeur Layton. Malheureusement pour lui, il s'avère que ce n'est pas le professeur qui dirige l'agence, mais plutôt sa fille, Katrielle Layton. Après s'être laissé convaincre par Katrielle, Simon décide de raconter son histoire. Il y a peu de temps, il a acheté une maison avec sa femme et ses deux filles, quand ces dernières ont mystérieusement disparu. Il pense que la maison est maudite et demande donc à Katrielle, Oliver et Sherl de retrouver sa famille avant qu'il ne disparaisse à son tour...

L'Agence reçoit la visite de Pastel, qui prétend que sa femme, Olivia, a été possédée. Katrielle invite Pastel et sa femme à raconter leur histoire. Pastel explique à Katrielle que ce phénomène serait causé par une robe. Un jour, alors qu'ils faisaient les magasins, Olivia avait remarqué la robe dans une vitrine, mais elle était beaucoup trop chère et le couple ne pouvait pas l'acheter. Peu de temps après, Olivia était tombée gravement malade, ce qui poussa son mari à lui achter la robe pour lui faire plaisir. Olivia semblait avoir retrouvé la santé peu de temps après. Mais une nuit, Olivia a tenté d'assassiner son mari, agissant comme si elle était possédée par une entité maléfique.

Une jeune femme, Liv, vient demander l'aide à l'Agence de détective Layton. En effet, elle affirme avoir vu le cadavre ressuscité de son mari Andy dans la nuit, alors que ce dernier est mort il y a plusieurs semaines lors d'un accident de travail. Katrielle, avec son imagination débordante, croit aussitôt à une histoire de zombie et se plonge dans l'affaire.

L'inspecteur Aspoirot demande à Katrielle son aide sur des vols en série, perpétrés par le voleur fantôme. Ce dernier annonce ces crimes à l'avance et arrive toujours à commettre son forfait sans que personne ne l'aperçoit.

M Frédéric qui été blessé par une flèche et devenu tout d'un coup un homme très chanceux. Mais cette chance étant partie, il demande à Katrielle de retrouver cette flèche de la chance.

Ula, une amie de l'Université de Noah demande à ce dernier de l'accompagner dans un étrange bus, qui remonte le temps 10 ans arrière. Katrielle intriguée par ce mystère décide de mener l'enquête.

RATMAN, le héros de Leo a soudainement disparu depuis 3 mois. Il sollicite l'aide de Katrielle pour le retrouver.

L'inspecteur fait appel à Katrielle une nouvelle fois suite à un vol à la Long Rolle Bank. Un vol sans effraction avec un butin de 100 millions de livres sterling !

Scola GULFRETSER, une des plus grande fortune de Londres, organise un banquet ou sera servie les mets les plus délicieux du monde. À cette occasion elle souhaite faire découvrir à tout le monde son animal de compagnie Petry. Mais voilà celui ci a disparu. Katterie accepte de ce charger de l'enquête pour pouvoir assister au banquet. Mais elle n'a que 6 heures pour retrouver l'animal.

La grand mère de Katrielle lui demande de retrouver le professeur Layton. Pour cela, elle dispose d'un indice pouvant l'aider à découvrir l'endroit où il se trouve.

The Agency attend the premier of a much-anticipated film, only to discover mid-scene that the moment of the climactic kiss has disappeared from the reel.

Relaxing on a public holiday, the Agency team become embroiled in a highly unusual case when a desperate Inspector Hastings pleads their aid in finding a last-minute gift for his wife's birthday.

Katrielle takes on a new case involving a young pianist who is being plagued by appearances of a doppelgänger.

Katrielle and the team are left puzzled when Hastings requests their help on a case where the culprit has already been uncovered.

The Agency receives a new mystery to solve when a young farmer details the unexplained appearance of strange patterns in their wheat fields.

Katrielle investigates a young girl on behalf of her concerned mother, who believes her daughter is able to predict the future.

Hastings turns to the Agency trio when London is menaced by a mysterious growling giant lurking in the fog.

Travelling on board the Molentary Express for a special solar eclipse tour, the team find their attention divided when clients old and new describe a sequence of strange events.

The team are summoned by a young heiress whose estate is seemingly being haunted by a host of ethereal apparitions.

Rosa returns to continue her story, and reveals the link between Katrielle's origins and the Professor's disappearance.

In search of sweets of legendary reputation, Katrielle is hooked when she is told that she will have to prove her connoisseur qualifications by locating the nearby store herself.

Katrielle is invited to the unveiling of Agency acquaintance and child genius Bengary's latest invention: Sketman John, a robotic renaissance-manservant.

One of London's famous "seven millionaires" requests the team's investigative attentions after discovering a love letter written by his much-adored daughter, Allie.

Hastings employs the Agency's efforts in the search for a hand belonging to Big Ben, in the hope of recovering it before the arrival of a foreign ambassador.

Katrielle joins an investigation at London's Riverside Festival into a tragic incident that took place on the banks of the River Thames, mirroring a local legend.

Ernest recounts the time he was accused of stealing valuable research papers on his first day at Gressenheller University, and his resultant first encounter with Katrielle.

The Agency team are forced to go on the run from the law after Katrielle finds herself the prime suspect in a murder investigation.

Katrielle finds yet another mystery on her hands when a celebratory treasure hunt held on a luxury cruise ship's inaugural voyage goes awry.

The Agency trio travel to the Scottish Highlands after receiving a request to investigate recent sightings of the famous "Nessie" creature on the waters of Loch Nem.

Strange goings-on in a suburban domicile lead the Agency's latest client to seek their advice as to whether or not his wife has become a witch.

Strange goings-on in a suburban domicile lead the Agency's latest client to seek their advice as to whether or not his wife has become a witch.

Katrielle takes on the task of reuniting a young woman with the object of her affections, a man who claimed to hail from another planet.

Bengary challenges the Agency team to solving their most ambitious case yet: a murder mystery from the realm of his own imagination.

On the tail of the fabled Relics, the Professor and Luke of eleven years prior close in on a shadowy figure, while Katrielle and co. trace their whereabouts in the present.

The paths of the parties past and present converge in Southampton, as the final hours before the duo's disappearance count down.

Angel Arrow CEO Bergman calls on the Agency after the label's four showcase dresses vanish two nights before the world's biggest fashion show.

The Agency is visited by Mintan's fellow farmworkers, seeking the team's help after a sudden personality change in their old friend transformed him from hard-working agronomist to obnoxious gambler sporting an improbable winning streak.

Katrielle joins a Scotland Yard blockade erected around a bridge due for demolition after Bengary's latest Sketman, Punch, takes up residence. With the giant robot incapable of vocal communication, Katrielle must figure out the reason behind its behavior to put an end to the standoff.

An Agencybound Katrielle receives a call from babysitter Kelly, whose concerns are centered around her latest assignation appearing to include an invisible infant.

Spurred by a horoscope warning that the only recourse to having "the worst day of the decade" might be to spend it with a friend, Katrielle decides to spend the day with Emiliana at a local café, unaware that the adroit analyst has her own plans. Emiliana challenges Katrielle to play at guessing the professions of their fellow customers, pitting the former's highly professional profiling skill squarely against the latter's esoteric and impulsive investigation methods.

In the wake of discovering a recurring phantom figure appearing in his images, London Times photographer Pete contacts the Agency, fearing that he has fallen victim to a curse.

Tired of being treated like the Agency dogsbody, Sherl jumps at the chance to conduct his own investigation into the reported death of a beloved member of the neighborhood pack.

The Agency trio are recruited by an old client with the goal of completing a challenging "virtual reality game".

After an incident involving a misunderstood "all-you-can-eat" restaurant opening and Katrielle's insatiable appetite, the eager investigator accepts the offer of a cook-off challenge to settle her debt.

Supernatural superfan Andrea, youngest of the seven millionaires, invites Katrielle and a selection of her acquaintances to compete in a game of "Ghost Escape".

The Agency trio's trip to the Marylebone Museum of Art to see the famous Mona Lisa takes a strange turn when Katrielle is informed that the museum's entire collection has been surreptitiously replaced with an array of Lisa-centric works.

Receiving an invitation addressed to her father requesting attendance of a puzzle-solving event hosted by the mysterious Ariadne, Katrielle and company find themselves reunited with all seven of the renowned London millionaires at the deserted mansion of a deceased magnate.

With the realisation that the Seven are hiding a secret, Katrielle's investigation takes an unexpected turn, and as she pieces together the mystery, the true identity of their host is revealed.

In the wake of having located Luke and the Professor, Katrielle's investigatory instincts refuse to let her rest, compelling the team to follow the trail of the mysterious "Aldebaran" to his palatial home in search of answers.

The two parties united at last, their long journey comes to a climactic conclusion in a fateful showdown at the Greenwich Observatory with the man behind the entire conspiracy.