The lost sword by Darrell Pitt

A Jack Mason Adventure. Text, 2015. ISBN 9781925240184
(Age: 10-13) Highly recommended. Science Fiction. Steampunk. Technology. Adventure. Mystery. Inventions. What a time to be alive; dragonflies and flowers for ships, whales for submarines. Jack, Scarlet and Mr. Doyle are dispatched on an extremely dangerous mission by the British Prime Minister. They are sent to Japan to recover the mysterious Kusanagi Sword lost for hundreds of years. With Nazi spies determined to foil their plans, the trio embark on a journey half way around the world, aboard the space steamer The Katsu. On board Dr Einstein discusses the amazing new biomechanic technologies - part animal and part machine and the scientific problems associated with The Hot Earth Theory.
Tokyo is an amazing city with huge skyscrapers, steam buses, airships and large dragonfly kagouro carriages to travel across the country. Part of their mission is to search for Mr. Doyle's stepbrother, a British spy and scoundrel who has gone missing. With a parchment map providing clues, Nazi agents chasing them and a young Japanese guide Hiro, they traverse Japan in search of the missing artifact. Travelling underwater in a whale submarine, Jack, Mr. Doyle and Scarlet's skills and deductive powers are tested when they encounter murder and mayhem trapped in Mizu the underwater city. Wearing a jelly fish diving suit - jellysuit, Jack shows incredible bravery facing a menacing shark, and overcoming his fear to save the day.
The lost sword has all the familiar elements set in a technologically advanced Japanese setting; derring-do acts, cunning plots, strange foods and new friends, fun and fast-paced action, evil villains and spies, even kidnapping. Darryl Pitt continues to amaze and excite as he brings this science fiction world to life.
Rhyllis Bignell