Sapphire & Steel is a British television science-fiction series starring David McCallum as Steel and Joanna Lumley as Sapphire. Produced by ATV, it ran from 1979 to 1982 and was primarily ATV's answer to the BBC's Doctor Who. The series was created by Peter J. Hammond, who conceived the programme after a stay in a haunted castle. Hammond also wrote all the stories except for the fifth, which was co-written by Don Houghton and Anthony Read.

The programme centres on a pair of interdimensional operatives, the titular Sapphire and Steel. Very little is revealed about their purposes or backgrounds in the course of the series but they appear to be engaged in guarding the order, if not the integrity of Time. In the series, it is explained that Time is like a corridor that surrounds everything, but there are weak spots where Time – implied to be a potentially malignant force – can break into the present and take things. There are also creatures from the beginnings and ends of time that roam the corridor looking for the same weak spots to break through.

These breaks are most often triggered by the presence of an anachronism, for example a nursery rhyme, a doctored photograph that mixes period and contemporary elements, or a house decorated to replicate a 1930s setting. Investigators will assess the situation and then, if intervention is warranted, Operators are assigned to deal with the problem by a mysterious unseen authority, to be assisted by Specialists if necessary.

The stories are generally quite cryptic, raising more questions than answers, and have an eerie air to them, being as much ghost stories as they are science fiction. The programme had been allocated a minuscule production budget, which led to the use of simple (but very effective) staging and minimal special effects, ultimately contributing to the uneasy atmosphere of the show. The ambiguous nature of the programme extends to its main characters. While Sapphire is portrayed as more affable and "human" than the no-nonsense, grim Steel, it is clear that their prime concern is to deal with the break in Time, sometimes over the safety of the humans caught in the incidents they investigate.

Each adventure usually starts with Sapphire and Steel simply showing up, seemingly out of nowhere, although sometimes they are already present when the story begins. They will then investigate and mingle with various humans, although it is nearly always the location the humans are in which is of the most interest: an old house which dates back to the 18th century, an abandoned railway station, a 1940s-era motorway café, and so on.

Although the series lasted over a period of four years, only six serials consisting of a total of 34 episodes were made, each episode lasting approximately 25 minutes. The first and second stories were shown in the summer of 1979, the second story's transmission interrupted by industrial action at the ITV network which led to a repeat of the story in 1979. The third and fourth stories were transmitted in January 1981, and the fifth in August 1981 with a sixth story "in the can" for future transmission.

By this time, production costs were increasing. The high profile and limited availability of the principal actors Lumley and McCallum meant that shooting was somewhat sporadic, and the programme's producers ATV were in the process of being reorganized into the new Central Independent Television, all factors which led to the series' demise. Central felt that viewers might mistake the new programmes for repeats of old ones, and broadcast the final, four-part story in late August 1982 to very little fanfare. The show has never been repeated on UK terrestrial television, but some episodes were shown on the satellite and cable station Bravo in the mid-1990s.

From Wikipedia