The cathedral used in this episode is at Chichester, in Sussex. But there is no garden where the ladies are seen working, and the opening scene (in which you see the garden in the foreground and the cathedral behind) is a montage.
Other scenes were also filmed in Chichester, such as when Rosemary and Laura go for a stroll to buy a dress.
The shot of Barbara, Laura and Rosemary driving down a small country lane in the Land Rover was re-used at the end of the episode The Invisible Worm. The problem was that the scene only had Rosemary and Laura in it, but you can clearly see three people sitting inside.
There are some problems with the locals on the town shoots looking at the camera, there is a noticeable appearance by an old woman wondering what is going on in the scene where Rosemary and Laura are discussing Nick's credit card.
When Laura locks herself in Eddie's car, wouldn't it have made more sense not to throw the keys away?
The giant sun outline at the end, doesn't cover all of the dead patches of grass.
The shot of Reynolds running through the grounds at night looks exactly the same as somebody running through the grounds in 'Arabica and the Early Spider'.
The shot of somebody running through the grounds before Rosemary is shot at, looks exactly the same as a shot from 'Sweet Angelica'