The genre-blending supernatural sci-fi fantasy Sapphire & Steel first appeared on British television screens in 1979. Produced by ATV, the series was conceived and for the most part scripted by Peter J. Hammond, an experienced TV writer of shows such as Dixon of Dock Green, Z-Cars, The Sweeney, The Gentle Touch and later The Bill, Wycliffe and Midsomer Murders. Broadcast at the end of the 1970s, the programme was an anomaly in that the series took time as a concept and presented it as having an evil dimension: the titular heroes, played by Joanna Lumley and David McCallum, are Interdimensional Operatives who are, it slowly emerges throughout the episodes, charged with ensuring the flow of time. This is all alluded to in the opening narration of each episode:
“All irregularities will be handled by the forces controlling each dimension. Transuranic heavy elements may not be used where there is life. Medium atomic weights are available: Gold, Lead, Copper, Jet, Diamond, Radium, Sapphire, Silver, and Steel. Sapphire and Steel have been assigned.”