Robert and his wife Katy decided to leave city life behind them after Robert was injured whilst trying to protect a witness in his care as he worked as a policeman. Susan Reynolds was fatally shot and Robert has been finding it hard to deal with the guilt he feels over the death of Susan. Robert and Katy now run a guest house, hidden away in the idyllic Lake District. After DCI Mark Maxwell shows up he suggests that the guest house is perfectly positioned to operate as a safe house. DCI Maxwell finds himself dealing with a family left reeling from a shocking assault and he calls Robert to see if he and Katy will take the family in and keep them safe. The Blackwell family adjust to life in a safe house and the man hunting the family is being investigated by Mark who turns to Robert for help and from within the safe house Robert starts his own investigation into the family.

Ali is given some devastating news and Robert has some difficult questions to ask her. Ali comes to an impulsive decision and Robert's methods are questioned. Robert quizzes Mark about a past decision. Michael manages to have a break-through in his hunt for the family and the police think that his arrest will happen soon.