Juno can't remember what happened before she was adopted by Cliff and Annie at age ten. Not until the night before their funeral, when she sees the ghostly black expanse of Luneford Tunnel in her dreams. Only then does she remember: Her mother left her there one day, alone, shivering, with a box of keepsakes and a goodbye note.
But where did she go? And why did she leave Juno on the banks of the canal by the tunnel?
Desperate for answers, Juno does the only thing she can think of: she returns to Luneford Tunnel. Hiring a canal boat along a stretch of water everyone warns is haunted, she navigates towards the last place she saw her mother, towards secrets, lies . . . and ghosts.