Tom becomes worried when his schoolteacher daughter, Susan, fails to arrive in Mt. Thomas. She was driving up from Melbourne to take up a temporary posting at the town's primary school. Dash and Adam, discover Susan's car, abandoned on the roadside. It has been involved in an accident with another car, also abandoned. No sign of either driver. Tom's concerns deepen when the owner of the other car is discovered to be Andy Maxwell, a man accused of murder a few years before. Bryan Maxwell, Andy's older brother, comes to the police station, anxious about Andy's failure to arrive at the family farm. Tom has just about convinced himself that Andy has done Susan harm when the missing two are found—they were only hiking for help after the side-swipe accident which Susan insists was her fault. To Tom's chagrin his daughter has struck up a friendship with this dubious young man and invites him home for dinner. Bryan, the brother, comes too. Conversation after the meal takes a sinister turn when