Edmund Thomas is dubbed by Michael Gough, as are a number of minor characters.
Writer John Tully explained that the setting was meant to be contemporary, but was changed to Victorian as the days of modern long distance communication would have made some of the plot twists too obvious (this and the fact they had already scouted a Victorian era home as suitable for use in the film).
The film's writer John Tully had to re-write the ending slightly as director James Hill was so adamant on using the distinctive organ in the film which was on display in the location home. The organ music also created a 'curtain call' scene for the cast at the end.
Gabrielle Hamilton (who plays Mrs Smee) is in fact the real life mother of Sarah Hollis Andrews (who plays Alice Harvey).