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.