Author: Leonard, M. G. Adventure stories (Children's / Teenage)Published on 12 February 2026 by PAN MACMILLAN (Macmillan Children's Books) in the United Kingdom as part of 'the Time Keys' series.Paperback | 272 pages, 40 black and white129 x 197 x 20 | 224g 'A complete triumph of imagination . . . readers are going to fall in love with this brilliant series' — A. F. Steadman, bestselling author of Skandar'A captivating adventure loaded with history and intrigue' – Abi Elphinstone''A cracking series with stunning illustrations' – Christopher Edge, bestselling author of Escape RoomThe 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 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 series:‘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
