Best Mystery Books for Teen Girls (2026): 4 Picks Compared
Four mystery picks for teen girls compared by grade level, reading age, page count and series, from a Christie-style whodunit to a spy thriller.

At a glance
Top picks
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When a teen who loves puzzles has finished her favorite series, the search for the best mystery books for teen girls starts with one question: whodunit or thriller? This list is for a teen reader and the parent or teacher buying for her, and it compares what each listing publishes.
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Quick picks
Best Overall The Agathas by Glasgow: Two girl detectives and a Christie-inspired puzzle, grade 9 to 12. Check price on Amazon
Best for Spy Stories The Squad by Barnes: A hacker teen pulled into a cheer squad that is secretly a spy team. Check price on Amazon
Best for Family Secrets Family of Liars by Lockhart: A summer of family secrets on a private island, for fans of We Were Liars. Check price on Amazon
Best Thriller Pick Girl, Stolen by Henry: A fast kidnapping thriller with a blind teen lead, in a 2012 reprint. Check price on Amazon
The picks
| # | Product | Shelf Score | Buy |
|---|---|---|---|
| 1 | The Agathas by Glasgow | 9.8/10 | Buy |
| 2 | The Squad by Barnes | 9.7/10 | Buy |
| 3 | Family of Liars by Lockhart | 9.6/10 | Buy |
| 4 | Girl, Stolen by Henry | 9.5/10 | Buy |

The Agathas by Glasgow
Two girls team up to find out what happened to a missing girl in a small town, a good fit for readers who like classic whodunits.
Pros
- Two girls lead the investigation, so the story stays with the detectives
- Grade level 9 to 12 and reading age 14 to 17 years agree with each other
- The description calls it Agatha Christie inspired, a clear fit for clue-based plots
Cons
- Book 1 of 2, so the story continues in a second book
- The description centers on a murder, so check it before buying for a younger teen
- At 432 pages it is long for a reader who wants a quick read

The Squad by Barnes
A teen hacker gets a mysterious note that pulls her into a cheer squad with a secret: its members are spies, a fit for readers who like spy stories.
Pros
- The lead is a hacker and karate black belt, which suits readers who like action
- Published March 3, 2026 by Delacorte Press, so the edition is new
- Grade level 7 to 9 is stated by the listing, a clear middle school to early high school range
Cons
- The description frames it as a spy story more than a whodunit
- The description hints the lead could be killed, so check the content for a sensitive reader
- Book 1 of 2, and the reading age is marked as from customers

Family of Liars by Lockhart
A summer on a private island brings a family's old secrets to the surface, a fit for teens who like family drama with a mystery edge.
Pros
- The description says the deluxe edition adds all-new exclusive content by E. Lockhart
- Grade level 7 to 9 and reading age 12 to 17 years are both stated
- The description calls it a prequel to We Were Liars, so fans get more background
Cons
- Series position is not stated, so it is hard to tell where it fits in a sequence
- The description mentions betrayal, terrible mistakes and sorrow, so preview the mature themes
- The reading age runs 12 to 17 years, a wide band that does not pin down one reader

Girl, Stolen by Henry
A blind sixteen-year-old is kidnapped and held for ransom, a fit for readers who want a fast, suspenseful thriller with a teen lead.
Pros
- Teen girl lead and a fast pace suit readers who want suspense
- The listing names the sequel, Count All Her Bones, for readers who want more
- The listing states both a grade level and a reading age, so the level can be checked
Cons
- The edition is a 2012 reprint, the oldest listing among these four
- Grade level 2 to 7 is a wide band, and reading age is marked as from customers
- The description covers kidnapping and a ransom, so preview it for a sensitive reader
As an Amazon Associate I earn from qualifying purchases.
More picks to compare
In Case I Go Missing by SwannFor teen readers who like amateur detectives and a missing-friend mystery.Check on Amazon
Whispers at Willowmere by TaylorFor readers 10 to 18 who like a horse farm mystery.Check on Amazon
Compare the picks
| Book | Shelf Score | Pages | Reading age or grade | Series | Amazon |
|---|---|---|---|---|---|
| The Agathas by Glasgow | 9.8/10 | 432 | Grade 9 to 12; reading age 14 to 17 years | Book 1 of 2 | Check price |
| The Squad by Barnes | 9.7/10 | 304 | Grade 7 to 9; reading age 12 to 16 years, from customers | Book 1 of 2 | Check price |
| Family of Liars by Lockhart | 9.6/10 | 336 | Grade 7 to 9; reading age 12 to 17 years | Not stated | Check price |
| Girl, Stolen by Henry | 9.5/10 | 240 | Grade 2 to 7; reading age 12 to 13 years, from customers | Book 1 of 2 | Check price |
Book details as published on each listing, collected 16 October 2026.
How we scored them
The Shelf Score weighs fit for a teen girl reader, contents and edition, value, and the listed reading age or grade level. All four picks list both a grade level and a reading age. The How we pick page explains the weights.
| Book | Shelf Score | Fit /35 | Contents /25 | Value /25 | Age/level /10 |
|---|---|---|---|---|---|
| The Agathas by Glasgow | 9.8 | 32 | 22 | 21 | 9 |
| The Squad by Barnes | 9.7 | 28 | 21 | 20 | 9 |
| Family of Liars by Lockhart | 9.6 | 26 | 21 | 19 | 9 |
| Girl, Stolen by Henry | 9.5 | 26 | 18 | 19 | 9 |
Scores run from 9.2 to 9.8: each book’s point total is placed on that range, so more points always means a higher score. Reading age or level counts on a list where at least one listing gives one, and a book whose listing gives none then scores zero on it. Where no listing gives one, the score is taken over the other 85 points. Books carry no warranty, so warranty is not scored.
How to choose the best mystery books for teen girls
Whodunit or thriller
The Agathas builds its plot around a missing girl and a set of clues, so it suits a reader who likes puzzles. The Squad and Girl, Stolen lean toward spy and kidnap plots, with a faster pace and fewer clues to solve. For more puzzle-style options, see best mystery books for teens.
Check the level and the edition
Compare the listed grade level with the reader’s current grade, and the reading age with how she reads. Older printings, such as the 2012 reprint of Girl, Stolen, may differ from newer ones, so check the publication date. For more girl-focused picks, see best YA books for girls.
Before you buy
- Check the series position: The Agathas, The Squad and Girl, Stolen are each listed as Book 1 of 2.
- Confirm the edition and publication date, since Girl, Stolen is a 2012 reprint and The Squad was published March 3, 2026.
- Read the description for mature themes: The Agathas centers on a murder, and Girl, Stolen on a kidnapping.
Frequently Asked Questions
Where should a teen start a mystery series?
Start with the title listed as Book 1 of 2, such as The Agathas (An Agathas Mystery). Confirm the series number on the listing before you order.
What reading level do these mysteries suit?
The Agathas lists grade 9 to 12 and a reading age of 14 to 17 years. The Squad lists grade 7 to 9 and a reading age of 12 to 16 years, marked as from customers.
Are these books part of a series?
The Agathas, The Squad and Girl, Stolen are each listed as Book 1 of 2. Family of Liars does not state a series position on its listing.
Related lists
See every Young Adult list and all Kids and Teens lists.
More lists: mystery books for girls, thriller books for girls and mystery books for young adults.