Book Series · 3 Books

Omega City Books

In order from Omega City to Infinity Base.

Omega City
The Forbidden Fortress
Infinity Base
Omega City
The Forbidden Fortress
Where the story begins

First Book in the Series

Omega City
Sale price
$674
Book #1 · Chapter Book · Ages 8–12 · 2015

Omega City

By Diana Peterfreund

A hidden city holds secrets that could save or doom them all.

324 pages
$6.99Save 4%
Paperback
Summary: Gillian Seagret is determined to prove her father's theories about a Cold War scientist's lost technology. With a mysterious diary page in hand, she and her friends venture into a forgotten underground city. As they navigate its dark corridors, they must uncover the truth before others who want the secrets buried forever catch up. Can Gillian save her father's reputation and reveal the hidden invention, or will the dangers of Omega City consume them?
In reading order

Omega City Series

3 books · Published 2015–2018

#1
Omega City
#1 in Series
Sale price
$674

Omega City

Chapter Book · Ages 8–12 · 2015

A hidden city holds secrets that could save or doom them all.

#2
The Forbidden Fortress
#2 in Series
Sale price
$1597

The Forbidden Fortress

Chapter Book · Ages 8–12 · 2017

Uncover hidden secrets and conspiracies before time runs out.

#3
Infinity Base
#3 in Series
Sale price
$1597

Infinity Base

Chapter Book · Ages 8–12 · 2018

Trapped in a hidden base, Gillian must uncover secrets to save her father and the world.

Good to know

Common Questions

How many books are in the Omega City series?

There are 3 books in the Omega City series. It began with Omega City in 2015, and the newest book, Infinity Base, was published in 2018.

What order should you read the Omega City books in?

Start with Omega City and follow the series order — the books above are numbered #1 through #3.

What ages are the Omega City books best for?

The series is best for ages 8–12, based on the age ranges of the individual books.

The people

The Creative Behind the Books

The authors and illustrators who bring Omega City to life.

01

Diana Peterfreund

Author

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