The Avengers · S3, E18
Mandrake
Steed attends the funeral of a former colleague and not only suspects foul play but is struck by the fact that the tiny, isolated Cornish churchyard contains the corpses of several worthies hardly to be associated with the area. His investigations lead to a sinister assassination bureau, Mandrake Investments, who bury poison victims in the churchyard because its proximity to an old tin mine means that the nature of the soil prevents the detection of the poison.
