The Blackwell family have to try and act like ordinary holiday makers, staying at the guest house. Sam Blackwell's car is discovered abandoned and there's growing concern for his safety. The police have discovered a connection between Sam and criminal Michael Collersdale. Robert is determined to discover the truth.

The investigation into Michael Collersdale has an unexpected twist and Robert has some concerning news for David and Ali. Sam and his brother decide to cross the lake and become involved in a shocking ordeal.