Stella and Tom's quest to solve the riddle of their neighbour's disappearing dog over the summer holidays soon leads to a boat buried under a grassy mound - and a tunnel that takes them to a secret lake. Who is the boy rowing towards them who looks so terrified? And whose are those children's voices carried on the wind from beyond the woods? Stella and Tom soon discover that they have travelled back in time to their home and its gardens almost 100 years earlier. Here they make both friends and enemies, and soon find themselves in deeper trouble than they ever could have imagined?