Just when Casey thinks her foster care duties are done, she’s asked to look after Sam, a troubled nine-year-old with a violent streak who drove his previous guardians to release him of their care. It soon unfolds, however, that this is no simple case. Determined to get to the root of Sam’s behaviour, Casey is committed to uncover his mysterious past only to find out something far darker than she ever imagined.

Harley, 13, has been sectioned under the mental health act after attempting suicide. She was spotted climbing the railings on a footbridge that crossed a busy motorway and pulled to safety by a member of the public. After six weeks in hospital, social services are looking for a short-term placement so she can be kept safe while family therapy takes place. Harley has a family - a widowed mother and an older sister, Milly, who left home with her long-term boyfriend just over a year ago.

Casey Watson is back, doing the job she does best - rolling up her sleeves and fostering the children who, on first meeting, seem like hopeless cases. But when she meets Miller and discovers the truth about his disturbing childhood, even Casey begins to doubt if this child will ever be able to accept love. Found naked and alone on a railway track, Miller was just five when he was first admitted into the care system.

It's the night before Christmas when Casey and Mike get the call. A 12-year-old girl, stuck between a rock and a hard place. Her father is on a ventilator, fighting for his life, while her mother is currently on remand in prison. Despite claiming she attacked him in self-defence, she's been charged with his attempted murder. The girl is called Bella, and she's refusing to say anything. The trouble is that she is also the only witness....

Angie, 6, and sister Polly, 4, are utterly distraught when they arrive to stay with foster carer Cathy Glass. Their older half-sister Ashleigh has accused their father of rape, and the two young sisters have been removed from home to keep them safe. Cathy tries to comfort the girls, but they are inconsolable. They just want their mummy and daddy, who they love dearly. The girls appear to have been well looked after, but as they settle and start to talk of life at home, it becomes clear something is badly wrong.