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The Impossible Gladiator: Join the Time Keys on their Roman adventure!
Not yet published
Expected 12 Feb 26'A complete triumph of imagination . . . readers are going to fall in love with this brilliant series' — A. F. Steadman, bestselling author of Skandar
The action adventure of Gladiator meets the time travel of Doctor Who in the third title of this epic series by bestselling award-winner M. G. Leonard. Perfect for 8 to 12-year-old fans of Adventures on Trains. Supports the key stage 2 curriculum. Illustrated throughout in black and white by Manuel Šumberac.
Sim, Jeopardy and Nelson are enjoying an amazing holiday in Rome, until they they are swept up in the mysterious disappearance of world-famous illusionist Kinetic. He vanished during a live broadcast from the Colosseum, but he never reappeared. When Kinetic’s sister finds a strange description in a history book of a gladiator who sounds uncannily like her brother, the friends are determined to help.
They travel through secret time doors to the spectacular — and deadly — Colosseum in Ancient Rome, but can the brave trio survive long enough to find Kinetic and bring him home?
The Impossible Gladiator can be read as a stand-alone novel, or enjoyed as part of the thrilling Time Keys series written by M. G. Leonard. Follow Sim, Jeopardy and Nelson's adventures in Ancient Egypt, Hunt for the Golden Scarab, and Viking Norway in The Legend of Viking Thunder.
Praise for the Time Keys
‘Classic and fresh – a breathtaking adventure’ - Eoin Colfer, author of Artemis Fowl
‘Fabulous, fast-paced and thrilling’ - Jonathan Stroud, author of the Lockwood & Co. series
‘A thrilling time-travel adventure’ - The Guardian
‘Fast, dramatic, exciting’ - Hannah Gold
‘Thrilling adventure packed with history, mystery and action’ - The Week Junior
The action adventure of Gladiator meets the time travel of Doctor Who in the third title of this epic series by bestselling award-winner M. G. Leonard. Perfect for 8 to 12-year-old fans of Adventures on Trains. Supports the key stage 2 curriculum. Illustrated throughout in black and white by Manuel Šumberac.
Sim, Jeopardy and Nelson are enjoying an amazing holiday in Rome, until they they are swept up in the mysterious disappearance of world-famous illusionist Kinetic. He vanished during a live broadcast from the Colosseum, but he never reappeared. When Kinetic’s sister finds a strange description in a history book of a gladiator who sounds uncannily like her brother, the friends are determined to help.
They travel through secret time doors to the spectacular — and deadly — Colosseum in Ancient Rome, but can the brave trio survive long enough to find Kinetic and bring him home?
The Impossible Gladiator can be read as a stand-alone novel, or enjoyed as part of the thrilling Time Keys series written by M. G. Leonard. Follow Sim, Jeopardy and Nelson's adventures in Ancient Egypt, Hunt for the Golden Scarab, and Viking Norway in The Legend of Viking Thunder.
Praise for the Time Keys
‘Classic and fresh – a breathtaking adventure’ - Eoin Colfer, author of Artemis Fowl
‘Fabulous, fast-paced and thrilling’ - Jonathan Stroud, author of the Lockwood & Co. series
‘A thrilling time-travel adventure’ - The Guardian
‘Fast, dramatic, exciting’ - Hannah Gold
‘Thrilling adventure packed with history, mystery and action’ - The Week Junior
273 pages, Kindle Edition
Expected publication February 12, 2026
10 people want to read
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Displaying 1 - 4 of 4 reviews
Review of advance copy received from Netgalley
Sim, Nelson and Jeopardy are back with Sim's mum, Callidora and Jeopardy's dad, Emmett. Calli and Emmett are no longer able to hear the time doors so they need Sim and Jeopardy to open them. They are in Rome for a opera, with Matteo Bloom who is playing Falstaff but who is also a time key. Calli hopes that Matteo might be able to explain why Sim can open time doors with a tuning fork rather than an instrument. They have all had to be very careful since they returned from the Viking times. The leader of the Council of the Keys, Kane Wolfe had been fixated with catching Calli but he thought Nelson was her son and that he wasn't a time key. Jeopardy however has had to wear a disguise every time she left her home in the Lasenby Rooms under Liberty's in London.
On the way to the Teatro dell'Opera, they notice missing posters - an illustionist, Kinetic, has gone missing from a stunt in Rome. His sister is on TV and putting up posters to plead for people to contact her if they know where he is.
At the Theatre they are in a second level box, provided by Matteo. When the Opera begins the children are watching, when Nelson sees something else through his binoculars - Penhooligan and Harridan from the Council of the Keys and they are looking straight at Matteo. They have their time keys, Kabir and Canticle with them. Emmett knows Matteo is safe till he goes off at the interval so he leaves with Jeopardy to warn him. Calli is going to watch the Council members from just outside of their box. But Emmett leaves Jeopardy in the foyer, where she sees Penhooligan and Kabir arrive. Kabir tells her to hide, then speaks really loudly when he says where they are going. Is he helping them?
They are going to the Pantheon - where they know there is a time door - to Ancient Rome.
But what do they want with Matteo? As Matteo escaped the clutches of the council members, he takes them to his apartment and explains he has been trying to help Soraya, who Calli has pushed into the apartment for following Matteo. She is the sister of Kinetic. She explains that he was supposed to disappear from the column outside the Colosseum, and reappear three minutes later at the Trevi Fountain. And then have dinner with his sister. He didn't reappear, and didn't turn up for dinner. Matteo and Soraya believe the driver sent to take Kinetic between the two places was Penhooligan. Soraya says that Kinetic described Penhooligan the night before after encountering three men sitting at a table in a piazza near the Pantheon, and something he said made them angry. But why would the council be interested in Kinetic, he's an illusionist not a time key. And where is he? Soraya is doing a PhD on teh poems of Martial a Roman poet from 80ce, and suddenly an odd line had appeared in a poem she knew by heart - a line she knew wasn't there. This line includes the name Latinus - the name she calls her brother. But Martial writes about real performers, so how could this line about a clown called Latinus be from Kinetic. Besides there is no door to 80ce, Emmett and Calli know tehre is a door to 121ce within the Pantheon, but that is it.
Can it be possible that Kinetic is in 80ce? But how did he get there? And where is the door?
Against the adults strict instructions, Sim, Nelson and Jeopardy decide to investigate the Pantheon door....
Utterly brilliant as I expected when I requested it. I loved the first two books because they were engaging and dragged you into the story very quickly. And so does this! The history lessons add to a story of intrigue and mystery. I forgot to mention just how good the illustrations by Manuel Sumberac are, add so much to the story when they fit so well.
These honestly should be in every school - I am campaigning - was kindly sent book 2 by the publisher, which I gave to the head to read so i could persuade her to buy the rest! Thanks to MacMillan publishers for allowing me to read this in advance on NetGalley.
On the way to the Teatro dell'Opera, they notice missing posters - an illustionist, Kinetic, has gone missing from a stunt in Rome. His sister is on TV and putting up posters to plead for people to contact her if they know where he is.
At the Theatre they are in a second level box, provided by Matteo. When the Opera begins the children are watching, when Nelson sees something else through his binoculars - Penhooligan and Harridan from the Council of the Keys and they are looking straight at Matteo. They have their time keys, Kabir and Canticle with them. Emmett knows Matteo is safe till he goes off at the interval so he leaves with Jeopardy to warn him. Calli is going to watch the Council members from just outside of their box. But Emmett leaves Jeopardy in the foyer, where she sees Penhooligan and Kabir arrive. Kabir tells her to hide, then speaks really loudly when he says where they are going. Is he helping them?
They are going to the Pantheon - where they know there is a time door - to Ancient Rome.
But what do they want with Matteo? As Matteo escaped the clutches of the council members, he takes them to his apartment and explains he has been trying to help Soraya, who Calli has pushed into the apartment for following Matteo. She is the sister of Kinetic. She explains that he was supposed to disappear from the column outside the Colosseum, and reappear three minutes later at the Trevi Fountain. And then have dinner with his sister. He didn't reappear, and didn't turn up for dinner. Matteo and Soraya believe the driver sent to take Kinetic between the two places was Penhooligan. Soraya says that Kinetic described Penhooligan the night before after encountering three men sitting at a table in a piazza near the Pantheon, and something he said made them angry. But why would the council be interested in Kinetic, he's an illusionist not a time key. And where is he? Soraya is doing a PhD on teh poems of Martial a Roman poet from 80ce, and suddenly an odd line had appeared in a poem she knew by heart - a line she knew wasn't there. This line includes the name Latinus - the name she calls her brother. But Martial writes about real performers, so how could this line about a clown called Latinus be from Kinetic. Besides there is no door to 80ce, Emmett and Calli know tehre is a door to 121ce within the Pantheon, but that is it.
Can it be possible that Kinetic is in 80ce? But how did he get there? And where is the door?
Against the adults strict instructions, Sim, Nelson and Jeopardy decide to investigate the Pantheon door....
Utterly brilliant as I expected when I requested it. I loved the first two books because they were engaging and dragged you into the story very quickly. And so does this! The history lessons add to a story of intrigue and mystery. I forgot to mention just how good the illustrations by Manuel Sumberac are, add so much to the story when they fit so well.
These honestly should be in every school - I am campaigning - was kindly sent book 2 by the publisher, which I gave to the head to read so i could persuade her to buy the rest! Thanks to MacMillan publishers for allowing me to read this in advance on NetGalley.
December 4, 2025
4.5 stars
Thanks to NetGalley and Macmillan Children's Books for the advanced copy of this title in return for an honest review.
This is book three in the Time Keys series, with the previous being:
1. Hunt For the Golden Scarab
2. The Legend of Viking Thunder
I love this series of M.G Leonard's - even if it is aimed at an audience that I am three times the age of. The first book - Hunt For the Golden Scarab - was fantastic and really re-ignited my love for Ancient Egypt. The second - The Legend of Viking Thunder - was still fabulous but my interests lie more in Egypt than with the Vikings, but it was still a glorious read.
I love that we get to revisit our core cast of characters from the previous books, but we also get new ones which help spice things up a bit, and it's in their interactions that the core cast get to shine.
Once again it is full of magic and adventure, challenges and danger, fun, love, and friendship.
The gladiator scenes were so pictorial you could clearly see it all so clearly and it was fabulous.
Considering the main cast are children, it can be difficult for a 32-year-old to identify with them and really get invested. But Leonard has given these children such depth and so much to do, they're so well rounded and just brilliant characters.
This one seems to have a lot more set in today's world, with the middle chunk set in the past, which gave an interesting comparison to the previous two, but it was still as good as if she'd spent more time in Ancient Rome.
The illustrations are, again, very good. There's not a huge quantity of them, but they really help add to the depth of the story.
I still believe these books are educational as well as entertaining. It's fun and exciting and kids will absolutely love it, but it's also full of teachings. Kids will first learn about the Ancient Egyptians, and then the Vikings, and now Ancient Rome, and hopefully it'll spark further learning.
I have loved this series as an adult and I would have loved it as a kid. And I really want many more instalments please.
I might have still preferred the first book, but this along with the previous two are brilliant reads. They're energetic and adventurous and original and just fabulous. I've read a number of her books now over the years and I have loved every one of them and have recommended them to people young and old.
Thanks to NetGalley and Macmillan Children's Books for the advanced copy of this title in return for an honest review.
This is book three in the Time Keys series, with the previous being:
1. Hunt For the Golden Scarab
2. The Legend of Viking Thunder
I love this series of M.G Leonard's - even if it is aimed at an audience that I am three times the age of. The first book - Hunt For the Golden Scarab - was fantastic and really re-ignited my love for Ancient Egypt. The second - The Legend of Viking Thunder - was still fabulous but my interests lie more in Egypt than with the Vikings, but it was still a glorious read.
I love that we get to revisit our core cast of characters from the previous books, but we also get new ones which help spice things up a bit, and it's in their interactions that the core cast get to shine.
Once again it is full of magic and adventure, challenges and danger, fun, love, and friendship.
The gladiator scenes were so pictorial you could clearly see it all so clearly and it was fabulous.
Considering the main cast are children, it can be difficult for a 32-year-old to identify with them and really get invested. But Leonard has given these children such depth and so much to do, they're so well rounded and just brilliant characters.
This one seems to have a lot more set in today's world, with the middle chunk set in the past, which gave an interesting comparison to the previous two, but it was still as good as if she'd spent more time in Ancient Rome.
The illustrations are, again, very good. There's not a huge quantity of them, but they really help add to the depth of the story.
I still believe these books are educational as well as entertaining. It's fun and exciting and kids will absolutely love it, but it's also full of teachings. Kids will first learn about the Ancient Egyptians, and then the Vikings, and now Ancient Rome, and hopefully it'll spark further learning.
I have loved this series as an adult and I would have loved it as a kid. And I really want many more instalments please.
I might have still preferred the first book, but this along with the previous two are brilliant reads. They're energetic and adventurous and original and just fabulous. I've read a number of her books now over the years and I have loved every one of them and have recommended them to people young and old.
Review of advance copy received from Netgalley
I received an eARC from the publisher through NetGalley in exchange for an honest review. It has not affected my opinions.
THE IMPOSSIBLE GLADIATOR continues these time-hopping adventure series.
As the title suggests, this entry takes us to Ancient Rome. There are actually two periods in Rome visited, one at the opening of the Coliseum and one about forty years later. The time doors are like nesting dolls in that sense.
There's so much to any time period and a book, particularly a Middle Grade novel with a limited page count, can only focus on so much. Here the focus is gladiatorial games. While there are gladiators, the book spends more time on the other parts of the games like beasts and acrobats. I liked that it didn't go down the well trodden path but looked at less common elements.
The earliest is illustrated by Manuel Šumberac. The illustrations are in a style very different to most MG books. It feels halfway between an old linotype image and an old photograph. It's dark and a little fuzzy in places, leaving people often in silhouette, rather than the crisp lines (and player shading) commonly used. It feels dark and mysterious, like people hiding in the shadows of history.
Three books in, we're starting to get hims of overall themes. The leaders of the evil council have broken a rule twice, so that's definitely something to keep an eye on. Plus the ending seemed to hint at the period to be visited next, Tudor England!
THE IMPOSSIBLE GLADIATOR continues these time-hopping adventure series.
As the title suggests, this entry takes us to Ancient Rome. There are actually two periods in Rome visited, one at the opening of the Coliseum and one about forty years later. The time doors are like nesting dolls in that sense.
There's so much to any time period and a book, particularly a Middle Grade novel with a limited page count, can only focus on so much. Here the focus is gladiatorial games. While there are gladiators, the book spends more time on the other parts of the games like beasts and acrobats. I liked that it didn't go down the well trodden path but looked at less common elements.
The earliest is illustrated by Manuel Šumberac. The illustrations are in a style very different to most MG books. It feels halfway between an old linotype image and an old photograph. It's dark and a little fuzzy in places, leaving people often in silhouette, rather than the crisp lines (and player shading) commonly used. It feels dark and mysterious, like people hiding in the shadows of history.
Three books in, we're starting to get hims of overall themes. The leaders of the evil council have broken a rule twice, so that's definitely something to keep an eye on. Plus the ending seemed to hint at the period to be visited next, Tudor England!
December 24, 2025
Feeling very lucky that I got to read this so early! I think MG Leonard is an incredible author who does storytelling brilliantly. Loved visiting Ancient Rome and learning all about life there! The magic and the awe of this series fills me with joy and knowing even more about the characters just makes me want more and more. That epilogue….. just brilliant!
Displaying 1 - 4 of 4 reviews