It starred Robert Vaughn as Harry Rule, Nyree Dawn Porter as the Contessa Caroline di Contini, and Tony Anholt as Paul Buchet.

It was Anderson's second television series to exclusively use live actors as opposed to marionettes following UFO, and his second to be firmly set in contemporary times post The Secret Service.

Despite not featuring marionettes or any real science fiction elements, The Protectors became one of Anderson's most popular productions, easily winning a renewal for a second series.

or Department S, resulted in plots that were rather simplistic, with motivation and characterisation sacrificed for action, owing to the writers having to cram as much as possible into a 25-minute timeslot and still produce gripping television.

[2] In Germany the series was known as Kein Pardon für Schutzengel (meaning "No Mercy for Guardian Angels") and in France as Poigne de fer et séduction ("Iron Fist and Seduction").

This made it more difficult for the show to make any impact in America, despite its popular American star, and this hurt its overseas sales.

According to Robert Vaughn's autobiography, there were many problems between the actor and both the show's financier, Lew Grade, and its co-producer, Gerry Anderson.

[citation needed] In a 1972 interview with The New York Times, he criticised the writing and casting, and said that The Protectors had failed to live up to his expectations, describing the production as "much below the American standard".

He added that the series "may have the redeeming feature of any escapist entertainment, that you can sit down for 22 minutes and watch people in pretty clothes run around shooting guns and so get your mind off your personal problems.