After Will's dad dies, his mum surprises him with a trip to Indonesia to help them get away from it all.
It's all going well until Oona, the elephant Will is riding along the beach one day, starts acting strangely.
And then a tsunami comes crashing in.
As Oona charges through the Indonesian forest, Will clings on for dear life, with no idea of where he's heading or exactly what he's leaving behind.
As hours stretch into days, and days into months, Will has to learn to adapt to his strange surroundings and work with Oona to survive.
But how long can it last, and what hope has a lone boy got of beating the jungle's many predators?
Will is the boy at the centre of the story, and it's easy to relate to him and the personal and practical struggles he faces.
You get a glimpse of the relationship he has with his mum and grandparents throughout the book, but the other main character is Oona.
Although she's an elephant, so a little short of conversation, she has plenty to say in other ways and makes a big impression.
Watch out for the evil villain of the tale too...
This book is told from Will's point of view and the way it's written makes it really easy to share in his emotions.
At times you'll feel as if you're riding through the jungle with him, so as well as laughing during the highs, prepare to shed a tear or two at the lows.
Any weak bits?
The beginning is really gripping, but then the action settles down for a bit and you might start to wonder if that's it.
Stick with it though as it'll soon have you sucked back into the jungle lifestyle and wondering what you'd do if you were Will when he faces his latest challenge.
It's a great book and once you get stuck in you won't want to put it down.
The ending doesn't disappoint either and you'll find yourself wondering what's happening in Will and Oona's world long after you've finished the story.
This reviews page is now closed. Here are some of the reviews you sent in.
"His books are amazing and I really want to buy this one. It must be just as good as the others"
Haseena, 10, Swindon, England
"As an American Indian poet, I think this book really mixes nature with suspense in a great way. 10/10"
Spoken River, 11, Ohio, USA
"It was the most amazing book I have ever read!"
"Wow! Michael's books are amazing - especially this one."
Joshua, 10, Manchester, England
"It was a book that had me on the edge of my seat. I read it all the time, no matter where I was."
Kristina, 11, Swansea, Wales
"It is a brilliant and very entertaining book. I wanted to read all night! I would recommend this book to ages 9-12."
Bonny, 9, Surrey, England
"I love Michael Morpurgo, I can't wait to read this book! I loved the Butterfly Lion. He is truly amazing."
Cerys, 10, Nottingham, England
"I am an adventurous bookworm, so this one sounds good to me!"
Harriet, 10, France
"I love Michael Morpurgo's books and he's such a fantastic writer. I'm sure that this will be a great book."
Revati, 12, London, England
"I have read his books for years this is probably another award-winning must-read!"
Lilly, 11, Glasgow, Scotland
"I think Michael Morpurgo is a very good author and I love his books!"
Lara, 10, Angus, Scotland
"It's really interesting and fun to read!"
Amy, 11, London, England
"I think Michael Morpurgo has a lot of imagination."
Talitha, 9, Kent, England
"After reading this review, I want to get this book defo!"
Ameena, 11, Wiltshire, England
"That was a great book."
Georgia, 11, North Yorkshire, England
"Best book ever and I have to tell you Oona is such a sweet little elephant!"
Ella, 10, London, England
"I love Michael Morpurgo, I can't wait to read this book! When will September come?!"
Hannah, 11, Hampshire, England
"I love this book loads, it's super! I read it in bed last night and I couldn't put it down!!"
Faith, 14, Cheltenham, England
"It looks great. I've got to get it for my birthday."
Thomas, 9, Essex, England