In an interview with star Honor Blackman she said that she feared the young child in the film would have damaging repercussions from having been in scenes with intense violence. She said that there was no physical danger at all, as the 'shard of mirror glass' was really a fake prop, but worried the sheer intensity of the actors would be disturbing to the child.
The trivia item below may give away important plot points.
In an issue of Photoplay George Cole recalled how he had first met Dennis Waterman on the set of Minder (1979). Waterman later corrected him by reminding him that he had once stepped over his dead body in this movie 8 years earlier.