While visiting her father in hospital, 13-year-old Isla meets Harry, the first boy to understand her and her love of the outdoors. But Harry is ill, and as his health fails, Isla is determined to help him. Together they watch a lone swan struggling to fly on the lake outside Harry's window.

Isla believes that if she can help the swan, she can help Harry. And in doing so, she embarks upon a magical journey of her own .