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.

Although Jodie is only eight years old, she is violent, aggressive, and has already been through numerous foster families. Her last hope is Cathy Glass. At the Social Services office, Cathy (an experienced foster carer) is pressured into taking Jodie as a new placement. Jodie's challenging behaviour has seen off five carers in four months. Despite her reservations, Cathy decides to take on Jodie to protect her from being placed in an institution.

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.

Tilly hates her stepfather, Dave. He abuses her mother, but she refuses to leave him. Frightened for her own safety, Tilly asks to go into foster care and is placed with Cathy. Tilly arrives with a graze on her cheek, and Cathy becomes increasingly concerned by Dave’s behaviour, especially when she learns he has been showering Tilly with gifts. While she’s busy looking after Tilly and trying to keep her safe, Cathy is also worried about her own daughter, Lucy.

When foster carer Cathy Glass is asked to foster Darcy-May, a two-day-old baby, she is very concerned. The baby is coming to her straight from the hospital and will have no contact with her teenage mother, Haylea. Even more worrying, she will be brought to Cathy with a police escort, as it’s vital her extended family don't know where she is.