Edge Of Darkness (1985)

Directed by Martin Campbell (GoldenEye, Casino Royale) and written by the late Troy Kennedy Martin, this was one political espionage thriller series that no one would forget in a hurry. The central themes were of bereavement and vengeance, but they expanded as the story went along with main hero Ronald Craven (Bob Peck) discovering more in the way of conspiracies and government corruption.

There were several fantastic set-pieces such as the death of Craven's only daughter, Craven confronting her killer McCroon, a pulsating foot pursuit where Craven escapes from a high security compound with vital evidence, Craven and Jedburgh breaking into Northmoor and the ending where Craven knows he's helped secure a victory despite on his last legs.

The BBC have never done anything as profoundly gripping since.