While haunted by memories of a failed arrest that allowed the Ripton Stalker to remain free, retired detective Inspector Huw Miller becomes suspicious of his enigmatic new neighbour Patrick Harbottle.

Huw's promise to his wife Alice to forget about Patrick and the Ripton Stalker comes under strain as his obsession grows. And despite Jenny's pleas to drop the matter, Huw sneaks into Patrick's house.

As the street becomes paranoid and Huw's desperation sets in, Alice gives her husband an ultimatum - prove Patrick is the Ripton Stalker or she's leaving him.

At home, Huw finds a photograph on the table. Patrick was here. Sending Alice and Margot away for their own safety, Huw vows to confront Patrick on his own.