At its centre is Franny Stone, a woman driven by an almost physical need to keep moving. She's crossed countries, abandoned homes and repeatedly left the people she loves, but her latest journey is different. Believing that the Arctic terns may be undertaking their final migration, Franny travels to Greenland and attaches tracking devices to three of the birds. She intends to follow them south to Antarctica, where she'll fulfil a promise connected to her husband Niall.
