A lost dog, a hidden time tunnel and a secret lake... A page-turning time travel adventure for ages 8-11. Now enjoyed by over 500,000 young readers! When Stella and her younger brother, Tom, move to their new London home, they become mystified by the disappearances of Harry, their elderly neighbour's dog. Where does he go? And why does he keep reappearing wet-through? Their quest to solve the riddle over the summer holidays...