The Secret Service

School For Spies (1x11)

Air date: Nov 30, 1969

Father Unwin discovers that a gang of bogus vicars are responsible for a series of sabotage attacks on military installations and vehicles. After one ofthe gang is hospitalised after their latest venture, Unwin masquerades as his replacement, a demolition expert, to infiltrate the gang, but he is soon exposed as an imposter.