A delightfully charming, super-cute and friendship-filled instalment in the award-winning Adventuremice series, from superstar collaborators Philip Reeve & Sarah McIntyre.

When Uncle Bernie turns up with his incredible Mechanical Mole machine, the Adventuremice go on a mission! Pedro and the crew burrow to an underground cave world, unlike anything they've ever seen. There are tiny, twisty trees, and even tinier pterodactyls! But there's also a HAMSTERSAURUS REX on the loose! Can the team save the nervous local cavemice from this giant predator, or is there more to the creature than meets the eye?

"By a celebrated team . . . takes us into the detailed dwellings of a delightful mouse community" - Sunday Times, praise for Adventuremice

"Absolutely stunning, beautiful, brilliant children's books. Instant classics" - Jamie Smart

"Superbly silly and highly endearing" - Waterstones' Perfect Paperbacks, praise for Adventuremice

"Irresistible . . . pictures that sparkle and fizz" - Books for Keeps, praise for Adventuremice

"Fun and heartwarming . . . this series is sure to be a winner" - BookTrust, praise for Adventuremice

"Reeve & McIntyre's wit, charm and silliness ooze throughout the story" - Just Imagine, praise for Adventuremice

"A book to inspire (day-)dreams and and great ambition. A small book . . . with a big heart" - Books For Topics, praise for Adventuremice