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Kirkus Reviews said of the first book: "wholesome shading to bland", but "well-stocked with exotic creatures and locales, plus an agreeable cast." Booklist Reviews called it a "exciting start to a promising series." The series' reception was largely positive. Books In The Keeper of the Lost Cities Series Book 1: Keeper of the Lost Cities (October 2, 2012) Book 2: Exile (October 1, 2013) Book 3: Everblaze (November 4, 2014) Book 4: Neverseen (November 3, 2015) Book 5: Lodestar (November 1, 2016) Book 6: Nightfall (November 7, 2017) Book 7: Flashback (November 6, 2018) Book 8: Legacy (November 5, 2019) Book 8.5: Unlocked (November 16, 2020) Book 9: Stellarlune (November 8, 2022) Book 10 : Untitled with unknown release date. The series was originally projected to conclude with an as yet untitled book 10, but Shannon Messenger has since said she is not sure if a book 11 will be required. The ninth book, the most recent installment, was released on November 8, 2022. The story has continued over ten books as of November 2022, with one book released each year, as well as Unlocked (book 8.5) and four short stories in limited editions. The main antagonist group of the series is the "Neverseen", a criminal organization at odds with the "Black Swan". They aim to shift the oligarchy under which the Lost Cities operate, with a central Council at its head. She eventually discovers that she has dangerous and illegal secrets hidden in her mind, planted there by the "Black Swan", a rebel group. She starts school at Foxfire, the school for Elvin nobility. She is forced to leave her human family behind and stay with an Elvin couple, Grady and Edaline Ruewen, who later adopt her. He tells her that she is an elf, and she must move to the Lost Cities, a hidden civilization where elves and other fantasy races live.
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She lives in San Diego, California until a teenager with the same power, Fitz Vacker, contacts her. The series tells the story of Sophie Foster, a twelve-year-old high school senior with the ability to read minds.
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Keeper of the Lost Cities is an upper- middle-grade fantasy series by Shannon Messenger that has appeared on the New York Times bestseller list for a total of ten weeks.
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