This is a story of something like survival. Sal planned it for almost a year before they ran. She nicked an Ordnance Survey map from the school library. She bought a compass, a Bear Grylls knife, waterproofs and a first aid kit from Amazon using credit cards she'd robbed. She read the SAS Survival Handbook and watched loads of YouTube videos.

And now Sal knows a lot of stuff. Like how to build a shelter and start a fire. How to estimate distances, snare rabbits and shoot an airgun. And how to protect her sister, Peppa. Because Peppa is ten, which is how old Sal was when Robert started on her.

Told in Sal's distinctive voice, and filled with the silent, dizzying beauty of rural Scotland, Sal is a disturbing, uplifting story of survival, the kindness of strangers and the irrepressible power of sisterly love - a love that can lead us to do extraordinary and unimaginable things.