A bogus medic changes his appearance so that her looks like Paul Dangerfield, then moves in on some of Paul's unsuspecting patients.

Paul Dangerfield and his colleagues at the practice become concerned when patients report home visits by a GP using their surgery's name as a calling card. With patients' lives seemingly put at risk, the police are asked to investigate. Paul is worried that his reputation is being violated by someone who seems to know his every move.