I was unsure whether to request this, as I had struggled a bit with the first novel, but I'm glad I did. I thoroughly enjoyed this read as Isaac and Hattie adventure across Paris in search of the forbidden atlas.
A great read.

This gripping sequel from Sam Sedgman finds us once again following the adventures of Issac and Hattie as they try to get to the bottom of another mystery. Having been invited to an event at the French National Archives in Paris to celebrate their achievements, Issac is all ready to give his speech when the lights suddenly go out, there is a shout and then a gunshot. What follows is an adventure that leads them both through the streets and tunnels of Paris in search of lost treasure and a missing sister whilst trying to work out who they can really trust.

I absolutely love anything Sam Sedgman writes. I adore the Adventures on Trains series he wrote with M.G. Leonard so I was excited to read his solo books too. I devoured The Clockwork Conspiracy and the sequel did not disappoint. Sam is incredible at painting a picture with his words. It is so easy to imagine being down in the tunnels and catacombs, crawling through spaces and trying to find a way in the dark. The illustrations sprinkled throughout were great and definitely added to imagining the scene.

One of my favourite things about Sam’s books though are all the little facts woven into the storyline. The Clockwork Conspiracy is full of them and this book has even more. Did you know the first metre was made of platinum? That the Eiffel Tower grows a few centimetres in summer because the metal expands in hot temperatures? Maybe you did but I love learning things whilst reading fiction so thanks Sam!

If you’re looking for an immersive middle-grade mystery with loveable characters, I highly recommend The Forbidden Atlas - and indeed anything Sam writes 😉

Sam Sedgman is an absolute genius at captivating and enthralling children (and adults!) Plots full of
twists and turns, unexpected happenings and so much more. Every book he writes goes straight to the top of my TBR pile and never fail to impress. Great story teller.

I loved this so much. I'd devoured the first book in the series as well as Sedgman's other books with MG Leonard. This sequel is twistier and darker, with even higher stakes than before. Sam just knows how to write exciting, smart, emotional books for young readers. What a talent.

Something about the Isaac Turner Investigates series hits a reading spot within that puts Isaac’s and Hattie’s adventures in a special place for me. I couldn’t help but be absolutely ecstatic when I saw this was my next read from Bloomsbury. This is a wonderful series that showcases the magic of humans and children without using magic at all, and before I dive into the review, that had to be said.

After The Clockwork Chronicles, I have to be honest, I didn’t know where this series would head next. My mind, unimaginatively, drew the conclusion that the series would focus on clocks and the next adventure would be in Prague or Canada to fulfill this. However, from page one, I was wondrously surprised to find there is no common trope except Isaac and Hattie’s incredible minds. The narrative of this novel, while still threaded with the nerdy elements of Isaac’s interests and the power of Hattie’s character, is completely different, and I ADORED it!

The addition of new characters, like Leon, and the further dive into characters like the duo’s parents, makes for such a brilliantly full world, and there’s no cast of characters I would’ve rather explored Paris with. Each of them brought out the best in one another, and that’s one of the things that makes this series continually powerful to read. I have yet to meet one character that I have not enjoyed (even the baddies!).

Now, onto the setting, I LOVE PARIS! The city holds the memories of a few special occasions for me, so it was sensational getting to see it in a new light that didn’t purely rely on the tourist destinations. Even though children may not yet tire of novels set in Paris being set solely at the Eiffel Tower and the Louvre, the parents supporting them with their reading may have, but Sam Sedgman has captured the flame of Paris so purely, I’d be almost 100% sure even a Parisian would adore it!

I thought this was even better than the first in this series The Clockwork Conspiracy. This time, Isaac and Hattie are in the beautiful city of Paris. Whilst attending a high-profile event where a theft and a shooting takes place, they end up on another action-packed adventure to find some long-lost treasure and make some new friends along the way.
Sam Sedgman cleverly uses history and places to bring this book to life!
I can see this being a hit in our library!
Thank you, @NetGalley_UK, for this advanced copy.

Sam Sedgman has proven himself to be a brilliant adventure writer first with his Adventures on Train series and now with his Clockwork Conspiracies series.

The Forbidden Atlas is the second in the series and is equally as brilliant as the first. Isaac and his dad love science, clocks and solving problems. Their first adventure had them embroiled in a major mystery and adventure in London involving Big Ben. This time, they are in Paris receiving an award for their bravery, along with Hattie, who is Isaac’s best friend and partner in crime.

When a gun goes off just before their presentation, Hattie and Isaac find themselves in the middle of a mystery involving a centuries old treasure hunt. While most would run away from the scene, Hattie and Isaac delve straight in and discover a boy running away, though when he is chased, he suddenly disappears. Those familiar with Paris know that deep under the city are the catacombs- a perfect place for hiding out.

Leon, the disappearing boy becomes integral to the treasure hunt and Isaac and Hattie work with him to discover who had the gun and what they want. It is surprising when you reach the end and realise just who the “baddie” is and what lengths they will go to in order to get their own way.

A fantastic adventure with some very suspenseful moments, tight spaces and two of the best characters out there! Love this series!

I so wanted to read this having loved The Clockwork Conspiracy which I read because I loved The Adventures on Trains books. Was I disappointed? No! Could it follow the Clockwork Conspiracy and keep up the adventure? Absolutely it could!

Isaac and Hattie are in Paris with Hattie's mum and Isaac's dad to collect an award for saving the world from those that wished to change time, by destroying the main clocks across the world.

But just as they are being introduced, a warning is heard and a shot rings out. The bodyguard (Omar) is shot supposedly protecting his boss Balthazar Blaise.
Diggory tells Isaac and Hattie to run. But they get out of the auditorium and see a boy running away...did he shoot Omar, they chase him but he gets away after a struggle. But Hattie has something he drops, can they find him from a receipt?
More importantly, why would a boy want to shoot Blaise?
They do find the boy, named Leon but his sister is missing which is why he was at the Archives that night but he swears he did not shoot, he was there for something else...something that could help him find Samira, his sister.
Follow the children on an adventure through Paris's catacombs on the search for a lost treasure connected to the item Leon stole. But they're not the only ones looking for it. When they find the 'key' they can find the treasure. But the treasure is housed in something which could cause problems across Paris. Samira knows this and so do those who are also looking for the treasure.
Flipping brilliant! Isaac and Hattie learn yet again how important friendship is, and so does Leon.
I so want these books in school! KS2 perfection.

THE FORBIDDEN ATLAS is another thrilling adventure full of intriguing facts and an exploration of systems that run the world that we often give little thought to.

THE CLOCKWORK CONSPIRACY was one of my favourite reads of 2024, a book I endlessly shoved at people since January of that year, so I was very much looking forward to the sequel. Luckily for me, it very much lived up to my expectations. I raced through this tale set across Paris.

Where THE CLOCKWORK CONSPIRACY looks at time and the standards around that, THE FORBIDDEN ATLAS explores the world of map making. From trap streets to how globes are made, this book is full of fascinating insights into maps and their history. I love how this series is focusing on the world around us, prompting readers to think about elements of everyday life that we might otherwise overlook.

I particularly enjoyed the cameos made by the Systeme Internationale (SI) in the form of the original metre and a fancy party at the BIPM (the body that oversees measurement science across the world.) They were very nice ways of linking the story to the exploration of measurement science in the first book.

Beyond the nerdery (which I adored), this book is also a thrilling adventure across Paris. Isaac and Hattie, along with new character Leon, are racing against an assassin to find a hidden map first - a map that leads to treasure and danger. There are so many puzzles layered into this book and plenty of puzzle solving from our intrepid heroes. It's a pacy tale full of action, with some heart stopping moments (as someone who's claustrophobic, the catacombs sequences were terrifying!) and a highly satisfying reveal about the hidden location.

I was so excited to see Hattie got to narrate this book alongside Isaac! It was so nice to see her thoughts and her grit, often literally pulling Isaac onwards when he started to overthink things. They're a very nicely balanced team.

There are some really nice visual touches to the book too. Each chapter starts with an illustration of a key scene and the chapter headers have little measurement scales on them that increase with each chapter (and yes, as soon as I get my hands on a physical copy, I will be measuring the scale to work out the increments.)

This book is exciting, thrilling, fast paced and has a hint of history. What better way to see Paris than through the eyes of Isaac and his friend as they try and solve a mystery in the catacombs under Paris.

The Forbidden Atlas is the thrilling sequel to Sam Sedgman’s The Clockwork Conspiracy – one of my favourite books published in 2024. Readers are transported to the intrigue and beauty of Paris as they race with Isaac, Hattie and Leon through dark streets and even darker catacombs in search of the key to an incredible mystery. Lives are at risk and time is short in this high-stakes, high-adrenaline adventure. Who can they trust? Only themselves.

The mesmerising opening sentences of the prologue portray a rare bookshop shining like a piece of amber. Immediately, I knew this was a story for me. The power of books, the wisdom of old booksellers, the fascination of an ancient map and the potential of hidden treasure grips readers from the very first pages. Questions of the identity of the villain and why they want the treasure snakes through the story allowing readers to search for clues and remain challenged until the end – the very elements of a book you can’t put down.

After saving ‘time’ in The Clockwork Conspiracy, Isaac and Hattie have been invited to a high-profile event at the French National Archives. As guests of honour, they are about to make a speech when the room is plummeted into darkness and a gunshot rings out. Not only has there been an assassination attempt but an important letter has been stolen – one written by King Louis XVI giving clues to the location of great treasure. To solve the mystery, they must navigate the catacombs of Paris – a complex network of underground tunnels. There is only one true map of the catacombs – The Forbidden Atlas.

The characters of Isaac and Leon are wonderfully unique with strength of voice. Isaac loves numbers and logic. He can solve almost any puzzle and is fascinated by facts. Hattie is overflowing with confidence, charm and intelligence. She has a style all her own and knows how to stand up for what is right. Their contrasting points of view develop the story from different angles providing depth and further intrigue. Leon is driven by loyalty and love for his sister. He knows Paris and its secrets. Together, this trio make a team that will be hard to beat – if only they can keep the interfering adults out of the way.

The Forbidden Atlas is a powerful sequel which leaves readers craving the next instalment. Isaac Turner is a brilliant hero and inspires young readers to use their minds to puzzle out any problem.

A huge thank you to Bloomsbury Children’s and NetGalleyUK for an early read of this amazing book!

The last thing you expect to happen at a celebratory event for high flyers is for the lights to go out. But that is just what happens when Hattie and Isaac's efforts are being recognised in France.

And while the sound of gunfire is understandably considered the result of a possible high profile assassination attempt, it turns out there is in fact something very different underway. And what that means is that Isaac and Hattie are off on an entire new adventure...

This is an excellent and lively sequel to the previous book and should be a great hit with the target readership. It gets 3.5 stars.

What a fantastic follow up to the first story. This one is set in France and is action packed and very fast paced. The children find themselves caught up in yet another crime, just when they were about to receive medals for their previous escapade in London. A really great new series that has already gained large numbers of fans.

While I’m not stupid enough to think that there is one story that every reader will fall in love with and choose as their utter favourite, there must be some that come pretty close and amongst those I suspect that adventure stories would feature pretty heavily. There is something thrilling about joining a protagonist as they find themselves facing deadly danger, whether it be on a quest to locate something, save a loved one or any one of countless other scenarios, particularly so if their surroundings are somewhere that the reader is familiar with or can envisage themselves being able to visit.

Here then, is a book that surely must fall into that category. A brilliant sequel to our hero Isaac’s first outing, The Clockwork Conspiracy, this new instalment takes us to Paris, home to the recent Summer Olympics, in a story that is fast-paced, action-packed and had me on the edge of my seat as he and best friend Hattie find themselves drawn into another gripping mystery.

Isaac is feeling distinctly uncomfortable when we meet him again. Invited with Hattie to the Musée des Archives Nationales in the French capital to receive acknowledgement of their efforts to save the world’s clocks in Book 1, he is well aware that his lack of the native language puts him at a huge disadvantage over his fluent friend when it comes to giving the speeches they are scheduled to deliver. When the time comes, Isaac and Hattie ready themselves as they are introduced by Balthazar Blaise, one of Paris’s richest individuals, but before Isaac can get into full swing the lights suddenly go out and a gun is fired.

As panic ensues, Isaac’s dad Diggory hurriedly ushers him and Hattie out of the room they are currently in, telling them to run to safety. Making good their escape, the two of them quickly become aware that there is someone else close by and that someone is possibly the shooter. When it becomes clear that it is in fact a boy, who appears to have stolen something and who swiftly flees the scene, Isaac and Hattie chase after him but lose him outside. Reporting what they have seen to the authorities, the friends are hugely frustrated when the Parisian police dismiss their accounts of what they have seen and decide to take matters into their own hands to track the boy down.

Before long Isaac and Hattie are drawn into a world of maps containing centuries-old secrets and the hidden underground network of tunnels that run under Paris as they hunt for a missing person and lost treasure. But there are others who are searching too and who are prepared to stop at nothing to prevent those who are in their way getting there first…

Having met and become firm friends in Book 1, here Isaac and Hattie come together to see their achievements marked without any expectation of finding themselves at the heart of another mystery. When they come across the boy after the shooting, Isaac very quickly realises that the crime is much more than just the attempted murder of a wealthy man and uses his acute sense of logic to work out just what that might mean. Buoyed by his success in finding his father previously, other than the language barrier that he occasionally meets here, he is so confident of his own and Hattie’s abilities in uncovering just what is going on that he never stops to wonder whether or not he should do so. Of course, the book would be very boring for us if he and his friend weren’t swept up in the mystery and this is one of the most exciting reads I’ve picked up in a while. I don’t want to say too much because of spoilers, but there is one part in the book where the sense of fear that the author creates is one that is palpable and had me, quite literally, on the edge of my seat as I read on to see how the situation was resolved.

Perfect for confident readers in Year 4 upwards, this would make a great standalone read as everything that the reader needs to know from the first book is covered but I would suggest that this is such a beautifully written series that you would be doing yourself a huge disservice if you skipped the introduction. I feel I should also comment on the internal illustrations at this point by David Dean which are outstanding, and which added hugely to my enjoyment of what is no doubt going to be one of my favourite reads of 2025.

I cannot wait to see to see what Sam Sedgman has in store for Isaac and Hattie next. The epilogue doesn’t give anything away but does leave the reader’s appetite for more well and truly whetted and to say I was gutted when I tried to find a date for Book 3 and failed is an understatement. Before then, my enormous thanks must, of course, go to publisher Bloomsbury and to NetGalley for my virtual advance read. The Forbidden Atlas publishes 27th February.

I have never been more excited to read a sequel. This is the second book in the 'Isaac Turner Investigates' series, following on from the 'The Clockwork Conspiracy'.

'The Forbidden Atlas' provides the same feeling of suspense and adventure as Isaac's previous adventure in London - now in Paris!

Isaac has been awarded a special honour for his achievements in London, however what was mistaken for a power cut turns into a captivating story with twists, turns and incredibly interesting moments.

Sedgman has always impressed me, whether writing a standalone novel or a creative piece with M.G Leonard. This is no different! A hugely enjoyable read, which I hope millions of children across the world will be introduced to when released.

5 stars! Great thanks to Bloomsbury for sending me a copy before release.

The second in the Isaac Turner investigates series, The Forbidden Atlas, sees Isaac and Harriet in Paris receiving an award for their heroics in The Clockwork Conspiracy (you can read my review here), however, things don't go as planned and an attempt on the life of businessman Balthazar Blaise sees Isaac and Harriet drawn into an underground world where a stolen letter and a missing map will lead to a long forgotten secret and a whole world of danger.

The Clockwork Conspiracy was hugely exciting and I've been looking forward to reading the sequel ever since I finished book 1! It was wonderful to be back with Isaac and Harriet again, especially as this time they are in Paris, a city dear to my heart. It was brilliant to be able to visualize everywhere they went (the catacombs and Père-Lachaise have long been on my list of places to visit and I'm now even more determined than ever to visit them next time I'm there).

The book is full of danger that will delight readers. Bouyed by their success in London, Isaac and Harriet are determined to get to the bottom of what is going on, which leads them to some incredibly dangerous situations (at times, I really felt for their parents!).

Like The Clockwork Conspiracy, The Forbidden Atlas is a book that excites and thrills, making it a read that is impossible to put down. With twists and surprises to keep readers on their toes, Sam has another guaranteed hit on his hands, which works as a stand-alone but is even better if you've experienced the adventure of The Clockwork Conspiracy.

Publishing 27/2, secrets, lies and daring all weave perfectly through the streets of Paris in this brilliant book that is even better than book 1. The Forbidden Atlas definitely needs to pre-ordered.