When Patrick Shepherd is called to talk a man named Saul down from a window-ledge, his world is shocked into new life. Saul looks just like Liam, Patrick's brother and childhood hero - who died years ago, or so he'd been told. Dissolute, charming and uncannily perceptive, Saul claims to be an angel on an mission to heal the fragile souls of a very particular group of people: Sarah, a clinic nurse trapped by grief; Tusa, an Angolan refugee who fears having her last hopes dashed if her daughter has to take HIV tests; her boyfriend Findlay, missing since he challenged a corrupt minicab boss; and Edward, accused of murdering the lost child the whole city has been searching for. For Patrick to understand the meaning of this visitation and get his own life back on track, he first must face his traumatic childhood in a council orphanage and the terrifying betrayal that tore the brothers apart.