On the Island of Ayrie, everybody knows everyone. They know each other's stories as they know every road, every hill and the coming of the tide. In the summer, there are bonfires to celebrate the migration of the puffins. Everything is familiar, nothing much changes, and for Tilda, nothing ever should – it is beautiful, it is perfect and it is home.

When newcomer Albie arrives at the island, Tilda wants to show Ayrie off – Albie wants her to leave him alone. She learns quickly that it'll take more than a tour and some seal viewings to win him around. Then, she remembers stories of the old island just an hour's boat ride away from the shore.

The old island is a death trap. The journey there is treacherous. Trips across to it are strictly forbidden. And there's a rumour it's haunted by the ghosts of those left there to die. But with all else having failed, the old island is the only way for Tilda to make Albie see what she sees in Ayrie.

Besides, it's a different kind of ghost that worries Tilda. The ghost that's been following her, now, since her brother left the island …