When animals speak, it's time humans listened . . . Harlon has been raised to protect her younger siblings, twins Ash and Xeno, both Listeners - those who can hear what's inside animals' heads, and even plant thoughts in their minds. When their home is attacked by the Automators, who aim to stamp out all Listeners, the children must flee for their lives. In a thrilling and dangerous adventure, they must journey alone across Rumyc to try to rescue each other - and fulfil the promise made to their mother that they will find the island lost in the deepest part of the ocean . . .