Highly intelligent but socially inept, Colin spends his free time collecting academic qualifications and searching for ways to meet women, until he stumbles upon a new technique that proves both potent and deadly. Police analyst Annabel is shocked when she discovers a decomposing body in the house next door and realises that no one, including herself, noticed her neighbour's absence. At work she finds data showing that such cases are frighteningly common in her own town and sets out to investigate, convinced she is on trail of a killer.