David McCallum, (Steel), played (as so often) a character of few (frequently terse) words: Joanna Lumley, at the height of her remarkable beauty, was Sapphire. The two actors worked very well together, and physically there was a certain resemblance between them. The voiceover for the effective opening scene was by a pre-Poirot David Suchet, but his name did not appear in the credits.
Each adventure is set in a particular locale - a house, railway station, restaurant, whatever - the action moves around the building but does not leave it. It is interesting to compare this series with the current computer-generated effects, and to see how much can be done with sound effects, lighting, camerawork, and, yes, acting.

Perhaps appropriately, in view of the underlying theme, the series was itself "out of its time": too late to build upon the mood of earlier shows such as the sixties' Star Trek and Time Tunnel, and too early to catch the sci fi boom of the late eighties and the present day. In 1996, subscribers to the Bravo channel were able to see the series. It was picked out for the Choice spot in the Radio Times of 4th April 1996, with the following comments:

"This intriguing science-fantasy series from 1980 starred Man from Uncle David McCallum and former Avenger Joanna Lumley as the enigmatic agents charged with protecting the world from time-disrupting forces. The bizarre storylines and clever camera work give the series its eerie feel. In this episode our heroes discover that time has become trapped in a photograph, and two people are imprisoned within it."

In the last few years, the series has continued to grow in popularity, and is now available on both DVD and video.

Details

Link: interview with P J Hammond (external site)
Sapphire and Steel website