Book Series · 6 Books

Gallagher Girls Books

In order from I'd Tell You I Love You, But Then I'd Have to Kill You to United We Spy.

The Gallagher Girls series is a set of 6 chapter books by Ally Carter, published between 2006 and 2013. Written for ages 12–18, most books run about 300 pages. Subjects across the series include spies, private schools, and self-evaluation.

I'd Tell You I Love You, But Then I'd Have to Kill You
Cross My Heart and Hope to Spy
Don't Judge a Girl by Her Cover
Only the Good Spy Young
Out of Sight, Out of Time
Where the story begins

First Book in the Series

I'd Tell You I Love You, But Then I'd Have to Kill You
Sale price
$1248
Book #1 · Chapter Book · Ages 12–18 · 2006

I'd Tell You I Love You, But Then I'd Have to Kill You

By Ally Carter

A young spy faces her toughest mission yet: navigating love while keeping her true identity hidden.

304 pages· 68,097 words· Est. 6.5 hour read
$12.99Save 4%
Paperback
Summary: Cammie Morgan, a spy-in-training at the secretive Gallagher Academy, excels in espionage but is baffled by romance. Fluent in fourteen languages and skilled in covert operations, she meets a boy who believes she's just an ordinary girl. As she juggles her double life, Cammie must decide if she can maintain a relationship without revealing her true identity. With her heart on the line, Cammie embarks on her most perilous mission yet—falling in love. Can she balance the demands of her secret world with the complexities of teenage romance?
In reading order

Gallagher Girls Series

6 books · Published 2006–2013

#1
I'd Tell You I Love You, But Then I'd Have to Kill You
#1 in Series
Sale price
$1248

I'd Tell You I Love You, But Then I'd Have to Kill You

Chapter Book · Ages 12–18 · 2006

A young spy faces her toughest mission yet: navigating love while keeping her true identity hidden.

#2
Cross My Heart and Hope to Spy
#2 in Series
Sale price
$1049

Cross My Heart and Hope to Spy

Chapter Book · Ages 12–15 · 2007

A young spy must clear her name and uncover secrets as danger looms at her elite school.

#3
Don't Judge a Girl by Her Cover
#3 in Series
Sale price
$1139

Don't Judge a Girl by Her Cover

Chapter Book · Ages 12–15 · 2009

Spy students face a deadly plot while protecting a vice-presidential candidate's daughter.

#4
Only the Good Spy Young
#4 in Series
Sale price
$958

Only the Good Spy Young

Chapter Book · Ages 12–15 · 2010

A young spy faces betrayal and danger as she uncovers secrets that could change everything.

#5
Out of Sight, Out of Time
#5 in Series
Sale price
$958

Out of Sight, Out of Time

Chapter Book · Ages 12–15 · 2012

A spy school student races to recover lost memories while evading a relentless enemy.

#6
United We Spy
#6 in Series
Sale price
$1049

United We Spy

Chapter Book · Ages 12–15 · 2013

Spies race to stop a terrorist plot that could change everything.

Good to know

Common Questions

How many books are in the Gallagher Girls series?

There are 6 books in the Gallagher Girls series. It began with I'd Tell You I Love You, But Then I'd Have to Kill You in 2006, and the newest book, United We Spy, was published in 2013.

What order should you read the Gallagher Girls books in?

Start with I'd Tell You I Love You, But Then I'd Have to Kill You and follow the series order — the books above are numbered #1 through #6.

What ages are the Gallagher Girls books best for?

The series is best for ages 12–18, based on the age ranges of the individual books.

Which Gallagher Girls book is the longest?

United We Spy (Book #6) is the longest book in the series at 68,843 words (320 pages).

Which Gallagher Girls book is the shortest?

Only the Good Spy Young (Book #4) is the shortest at 56,153 words (288 pages).

The people

The Creative Behind the Books

The authors and illustrators who bring Gallagher Girls to life.

01

Ally Carter

Author

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