- Producers: Gerry Anderson and Reg Hill
- Directors: [John Hough], Don Chaffey, Jeremy Summers, Roy Ward Baker,
- Director of Photography: Brendan J. Stafford & Frank Watts
- Art Director: Bob Bell
- Script Editor: Tony Barwick
- Robert Vaughan - Harry Rule
- Nyree Dawn Porter - Contessa Caroline di Contini
- Tony Anholt - Paul Buchet
- Anthony Chinn - Chino
- Yasuko Nagazumi - Suki
Not all regulars were in every episode and Vaughan was absent from at least one.
Three inexplicably affluent international private detectives/troubleshooters who were charged with ensuring the protection of innocents. They belonged to an organization called The Protectors and were based in London. Harry lead the group, The Contessa lived in Italy (when she wasn't working with Harry); She ran her own detective agency that specialized in exposing art frauds and recovering stolen art. Paul Buchet worked out of Paris, and was the group's researcher and gadget specialist. Adventures ranged from simple kidnapping to convoluted cases of international intrigue. These characters were all wealthy and drove exotic cars of the era including the Citroën SM and Jensen Interceptor. >
- 2000 ft To Die
- Brother Hood
- Disappearing Trick
- Your Witness
- The Quick Brown Fox
- The Numbers Game
- Triple Cross
- A Kind Of Wild Justice
- One And One Makes One
- See No Evil
- Balance Of Terror
- King Con
- The Big Hit
- The First Circle
- ...With A Little Help From My Friends
- For The Rest Of Your Natural...
- The Bodyguards
- A Case For The Right
- A Matter Of Life And Death
- It Could Be Practically Anywhere On The Island
- It Was All Over In Leipzig
- Ceremony For The Dead
- The Bridge
- Fighting Fund
- Goodbye George
- The Last Frontier
- Baubles Bangles And Beads
- Burning Bush
- Border Line
- WAM Part One
- WAM Part Two
- Dragon Chase
- Zeke's Blues
- A Pocketful Of Posies
- Sugar And Spice
- The Tiger And The Goat
- The Insider
- Route 27
- Edgwarebury Hotel, Elstree, Hertfordshire, UK.
- Barnet Lane, Elstree, Hertfordshire
- High Canons, Well End, Hertfordshire, UK
- 2 Courtfield Mews, Sth Kensington, London, UK
- Music Composed and Directed by John Cameron
- Theme Music & Lyrics by Mitch Murray & Peter Callender
- In the Avenues and Alley Ways - Tony Christie (reissued in 2000)
- Released to region 2 DVD in 2003
- North American DVD
- Season 1 September 2003
- Season 2 May 2004.
- The series was shot on 16mm film rather than the usual 35mm, despite its exotic capital and major city locations, as well as its affluent characters
- The series was unusual for Anderson in that it did not entail any significant Sci-fi or special effects.
- Nyree Dawn Porter's role was originaly to have been a male character.
- Anderson claimed Vaughn acted like a Hollywood prima donna and refused to get on with the other actors.
- Vaughn claimed that he felt the series was "tasteless junk", and that he couldn't understand the scripts either before or during shooting.
- Vaughn was given the opportunity to direct one episode himself - #23 in production order,
- Grade called it the worst episode he'd ever seen of anything.