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The Undetectables series - The Unsolvable Case

By Courtney Smyth
Series: The Undetectables
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Brief Description
It’s three days until Samhain, and the Undetectables are going to die. No longer taking magical cases (not that anyone would hire them), they’ve well and truly given up the ghost. Meanwhile, Theodore — the relinquished ghost in question — is on the run. Wanted in... Read More
Format: Paperback / softback
$2899
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Releases 2nd February 2027 (Approx. Date) Pre-order  "The Undetectables series - The Unsolvable Case" now to secure your copy from our first shipment

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The queer witchy fantasy murder mystery series concludes in one last mystery for Mallory, Cornelia and Diana, as they have to solve their biggest, and most important case of all - who killed Theodore. Perfect for fans of supernatural mysteries and cosy crime by authors such as Ben Aaranovitch, Josiah Bancroft and Tammie Painter.

Book Hero Magic formatted this description to make it easier to read. While it's new and still learning, it may not be perfect - your feedback is welcome! Description

It’s three days until Samhain, and the Undetectables are going to die. No longer taking magical cases (not that anyone would hire them), they’ve well and truly given up the ghost. Meanwhile, Theodore — the relinquished ghost in question — is on the run. Wanted in connection with the Undetectables’ last case, he’s hiding in the last place anyone would think to look, keeping secrets (badly) and forming unlikely alliances (slightly less badly).

When a copycat killer emerges and history appears to be repeating itself, the Undetectables are called up for one last case. Mallory, Diana and Cornelia find themselves in a final race against the clock – but this time, the whole of Occulture is at stake.

The Unsolvable Case by Courtney Smyth is an exciting addition to the gripping Undetectables series, filled with mystery, intrigue, and a touch of the supernatural.

Series: The Undetectables

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  • The Undetectables series - The Undead Complex
    A witty, witchy fantasy murder mystery packed with ancient magic and fiendish puzzles. Mallory, Diana, Cornelia, and Theodore are hired to solve a murder on a TV shoot by the victim herself. Perfect for fans of supernatural mysteries and cosy crime by authors such as Ben Aaronovitch, Josiah Bancroft, and Tammie Painter. Five months after the events of The Undetectables,...
    By Courtney Smyth
    Paperback
    $2899
    Available
    Ships in 4-6 weeks
  • The Undetectables series - The Unsolvable Case
    Pre-order
    The Undetectables series - The Unsolvable Case
    It’s three days until Samhain, and the Undetectables are going to die. No longer taking magical cases (not that anyone would hire them), they’ve well and truly given up the ghost. Meanwhile, Theodore — the relinquished ghost in question — is on the run. Wanted in connection with the Undetectables’ last case, he’s hiding in the last place anyone would...
    By Courtney Smyth
    Paperback
    $2899
    Pre-order
    Out 2 Feb 2027

Book Details

INFORMATION

ISBN: 9781835412237

Publisher: Titan Books Ltd

Format: Paperback / softback

Date Published: 22 September 2026

Country: United Kingdom

Imprint: Titan Books Ltd

Audience: General / adult

DIMENSIONS

Spine width: 55.0mm

Width: 130.0mm

Height: 198.0mm

Weight: 255g

Pages: 496

Collections

Coming Soon in Fiction Cosy Crime Courtney Smyth Crime & Thriller Fantasy Fiction General Fiction Pre-order Books Pre-Order Science Fiction & Fantasy Pre-orders Pre-orders by Release Date Sci-Fi & Fantasy Series: The Undetectables

About the Author

Courtney Smyth (they/them) is a chronically ill writer of stories, both long and short, from Dublin, currently living in the West of Ireland. They have had a number of short stories published in Paper Lanterns Literary Journal, and appeared in The Last Five Minutes of a Storm anthology from Sans Press. They have been writing about ghosts, demons and murders since they were ten and have no plans to stop. They can be found yelling about books on Twitter and Instagram @cswritesbooks.

Also by Courtney Smyth

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  • The Undetectables
    Be gay, solve crime, take naps - A witty and quirky fantasy murder mystery in a folkloric world of witches, faeires, vampires, trolls and ghosts, for fans of Magic for Liars by Sarah Gailey and T. J. Klune's Under the Whispering Door. A magical serial killer is stalking the Occult town of Wrackton. Hypnotic whistling causes victims to chew their...
    By Courtney Smyth
    Paperback
    $2899
    Available
    Ships in 4-6 weeks
  • The Undetectables series - The Undead Complex
    A witty, witchy fantasy murder mystery packed with ancient magic and fiendish puzzles. Mallory, Diana, Cornelia, and Theodore are hired to solve a murder on a TV shoot by the victim herself. Perfect for fans of supernatural mysteries and cosy crime by authors such as Ben Aaronovitch, Josiah Bancroft, and Tammie Painter. Five months after the events of The Undetectables,...
    By Courtney Smyth
    Paperback
    $2899
    Available
    Ships in 4-6 weeks
  • The Undetectables series - The Unfathomable Curse
    A witty, witchy fantasy murder mystery packed with ancient magic and fiendish puzzles. When Cornelia’s twin sisters are taken by the Wickermere Reaper, Mallory, Diana and Theodore must race against time to uncover the buried secrets of the Broadwicks before it’s too late. Perfect for fans of supernatural mysteries and cosy crime by authors such as Ben Aaranovitch, Josiah Bancroft...
    By Courtney Smyth
    Paperback
    $2599
    Available
    Ships in 4-6 weeks

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