Keeper of the Lost Cities

Keeper of the Lost Cities is an upper-middle-grade fantasy series by Shannon Messenger that has appeared on the New York Times Best Seller list for a total of ten weeks.

Plot summary
The protagonist of the series, Sophie, is a twelve-year-old elf with telepathy who lives in San Diego, California with a human family.

While on a school field trip, another elf teenager, Fitz tracks her down and reveals that she is a elf. He discusses the reality of their world with Sophie and tells her that she must move to the Lost Cities, a place unknown to humankind where elves, trolls, ogres, goblins, gnomes and dwarves live in harmony. She is forced to leave her human family behind and stay with an elvin couple, Grady and Edaline, who later adopt her. She starts school at a noble elvin academy named Foxfire.

The main conflict in the series is between the Black Swan, a rebel organization, and the Neverseen, a group of criminal extremists. Sophie learns that the Black Swan are her creators, and that her old neighbor from the human world, Mr. Forkle, is the director of the Black Swan's Project Moonlark, in which she was created. Her biological parents are unknown due to catastrophes that could be created if she finds out. The parents could face scorn and be punished for being involved in Project Moonlark due to its secretive and illegal nature. Later in the series, Sophie is desperate to find out who her biological parents are, believing it to be the best solution, otherwise she would be unmatchable, meaning she would be looked down upon if she married someone not on her match list.

Main series
The main series currently consists of 9 released full books, along with Unlocked, a novella between Legacy and Stellarlune.
 * 1) Keeper of the Lost Cities (October 2, 2012)
 * 2) Exile (October 1, 2013)
 * 3) Everblaze (November 4, 2014)
 * 4) Neverseen (November 3, 2015)
 * 5) Lodestar (November 1, 2016)
 * 6) Nightfall (November 7, 2017)
 * 7) Flashback (November 6, 2018)
 * 8) Legacy (November 5, 2019)

8.5. Unlocked (November 17, 2020)
 * 1) Stellarlune (November 8, 2022)

9.5. Unraveled (November 12, 2024) The tenth installment in the series was originally scheduled for 2023 but does not have a publication date. Additionally, book 9.5, Unraveled is a planned installment between Stellarlune and the tenth installment.

Graphic novel adaptation
A graphic novel adaptation of Book 1 was released on November 7, 2023, and is divided into two halves following the main storyline of the original book. The author is Celina Frenn and the illustrator is Gabriello Chianello.

Reception
The series has a largely positive reception. Kirkus Reviews said that the first book was "wholesome shading to bland, but well-stocked with exotic creatures and locales." Booklist Reviews called it a "exciting start to a promising series."

Film adaptation
On January 11, 2021, it was announced that Ben Affleck would be directing an adaptation of Keeper of the Lost Cities for Walt Disney Pictures.

On April 18th, 2024, it was announced that Warner Bros. had landed the rights to the Keeper of the Lost Cities adaptation, with Emma Watts serving as producer and Messenger serving as executive producer.

Characters

 * Sophie Elizabeth Foster: The main protagonist of the series. She is a Telepath, Inflictor, Polyglot, Teleporter, and Enhancer, some of which abilities are not known to her at the beginning of the series. Her genes, sourced from Councillor Oralie, an unknown elf, and alicorn DNA, were tweaked by the Black Swan, giving her unusually powerful abilities. She was raised by humans after her experimentation and brought back to the Lost Cities at the age of twelve to complete her education at Foxfire Academy in addition to being adopted by Grady and Edaline Ruewen. She later begins a relationship with Keefe Sencen.
 * Keefe Sencen: Sophie's close friend as well as boyfriend (as of book 9, Stellarlune). He is an Empath, allowing him to detect others' feelings. Unlike other Empaths, he can sense emotions without physical contact. In Unlocked, he also becomes a Polyglot, capable of speaking all languages, and manifests two unnamed abilities. His mother, Gisela, is one of the series' main antagonists. He is known for his mischievous ways, such as "the Great Gulon Incident" which is mentioned, but never explained, multiple times throughout the series. He often jokes and teased but it is later revealed that he just uses it to hide how much his parents have abused him. Throughout the series, he mostly aims to discover his "legacy", a term coined by his mother, Gisela.
 * Fitzroy "Fitz" Avery Vacker: Sophie's close friend. He is a highly skilled Telepath and becomes Sophie's Cognate, making them a close telepathic pair. After he and Sophie broke up, their Cognate relationship was damaged. He belongs to a prominent family of Elvin nobility. He is sometimes known for his temper issues, relying on anger when he is not sure how to feel, almost murdering his brother Alvar at one point.
 * Dexter "Dex" Alvin Dizznee: Sophie's best friend; also a talented alchemist with Technopathy, the ability to manipulate technology. He was sometimes forced to make devices by the Council, for example, the Ability Restrictor in Everblaze.
 * Biana Vacker: Sophie's enemy-turned-friend and Fitz's younger sister. She is a Vanisher, allowing her to turn invisible. She is often found sneaking around and listening in on people's conversations. She is shown to be popular in the series.
 * Tam Dai Song: Sophie's friend, a previous student at Exillium, a school for banished and or "unruly" elves. He is a Shade, capable of manipulating shadows. Because of his ability, he is rarely trusted by strangers. In Flashback, he is shown to be able to manipulate an element called "Shadowflux," shown to be very powerful through the later books.
 * Linh Hai Song: Tam's twin sister, also a previous student at Exillium. She has the ability of Hydrokinesis, the ability to control water. She is known as "the girl of many floods" due to the fact that she caused many floods while mastering her Hydrokinesis, causing her to be banished from the Lost Cities.
 * Marella Redek: Sophie's gossipy friend with a rare and illegal special ability, Pyrokinesis, letting her control fire.
 * Stina Heks: an Empath who used to bully Sophie but changed her views on Sophie after Neverseen. Her family is affiliated with and supports the Black Swan. She is a member of Team Valiant.
 * Wylie Endal: The son of Prentice Endal, a key member of the Black Swan. He is a Flasher, which means he can sense and manipulate the colors of light. He also lived with his adoptive father Tiergan after his father's memory break.
 * Maruca Chebota: Wylie's cousin, a Psioniopath (meaning that she can create force fields), and Biana's old friend.
 * Mr. Forkle: The leader of the Black Swan and a fatherly parental figure to Sophie.
 * Grady Ruewen and Edaline Ruewen: A couple who are Sophie's adoptive parents. Grady works as an Emissary. Edaline is a Conjurer and rehabilitates animals.