The Fever Code (The Maze Runner #0.6, #5) by James Dashner
Publisher: Chicken House
Goodreads Summary: 
All will be revealed in the fifth book in James Dashner’s #1 New York Times bestselling Maze Runner series. This is the story that fans all over the world have been waiting for—the story of how Thomas and WICKED built the Maze. You will not want to miss it.

Once there was a world’s end.
The forests burned, the lakes and rivers dried up, and the oceans swelled.
Then came a plague, and fever spread across the globe. Families died, violence reigned, and man killed man.
Next came WICKED, who were looking for an answer. And then they found the perfect boy.
The boy’s name was Thomas, and Thomas built a maze.
Now there are secrets.
There are lies.
And there are loyalties history could never have foreseen.
This is the story of that boy, Thomas, and how he built a maze that only he could tear down.
All will be revealed.

A prequel to the worldwide Maze Runner phenomenon, The Fever Code is the book that holds all the answers. How did WICKED find the Gladers? Who are Group B? And what side are Thomas and Teresa really on? Lies will be exposed. Secrets will be uncovered. Loyalties will be proven. Fans will never see the truth coming. Before there was the Maze, there was The Fever Code.
Rating: 3.5 Stars
In this prequel to The Maze Runner we journey back in time to before the Maze trials, and how WCKD begun. (begun or began?) We watch as some lose their sanity and the way they turn out after they become infected. The Fever Code starts from being separated from their families, to entering the maze. Some of TMR's main characters' old names are revealed too.

Thomas is quite different from TMR Thomas. he is involved in a web of lies, however he doesn't realise it. He is a lot more naive and innocent as well. Teresa is loyal and believes in the cause, yet her loyalties aren't always clear for others. I was ecstatic when Newt appeared in the book, and some of his history and family is revealed. As we know, the maze is no bloodless affair, and through Thomas's observations we see the Maze before TMR.

Ava Paige's character intrigued me throughout the book. She begins as a kindhearted secondary mother to Thomas, hiding her true intentions and gaining his trust. The clues are present, but both Thomas and I ignored the flashes of her other side when she got impatient. I think her character had the best development overall, with all the hidden agendas only hinted at through Thomas's third person perspective.

I enjoyed this book so much more than The Kill Order, which is a relief. I didn't love it, but the adventure parts of the story were well written. I disliked that WCKD knew everything and no reasons or explanations were given when they revealed their knowledge because I thought this was unreasonable and they couldn't know "everything". The Fever Code is a must-read for all TMR fans as it contains the backstory you've all been dying to hear.
Purchase Location: Borrowed From School Library
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Recommended for: Anyone who has read The Maze Runner, this could also be an introduction to The Maze Runner series.