Continuity mistake: When Laura finds the hammer with blood and hair on it, Rosemary finds the constable and tells him where the hammer is. When we first see the constable's car, it's in a ditch. But when he gets into it and drives away, it's no longer in the ditch, but beside the road.
Orpheus in the Undergrowth - S2-E2
Plot hole: At the very end, Julia calls Matt, a policeman, at Helena's place, to tell him to come and help his mother and Rosemary who are being held against their will. But Matt doesn't have a mobile, so how did Julia know he was at Helena's place, so she could ring him there and save the day? No-one knew he was at Helena's and it's the middle of the night. Matt should have been in bed asleep.
Orpheus in the Undergrowth - S2-E2
Other mistake: When Rosemary comes back from seeing her old college professor, she comes in from the garden, but Julia's place - this is where Rosemary and Laura are staying - is on the first floor; there's no access to her place from the garden. Rosemary should have gone to the front door, on the street.
Orpheus in the Undergrowth - S2-E2
Plot hole: When Jeremy is found dead from a heart attack, for some reason, the girls talk about him taking something that caused his heart attack, or someone giving him something to cause his heart attack. People have heart attacks all the time, and Jeremy had "a dodgy ticker", so there's no reason for them to only think it's a "suspicious" heart attack.
Swords into Ploughshares - S2-E7
Continuity mistake: Laura is handed a cup of tea that is only half-full. But when she puts the cup down, it's full.
Orpheus in the Undergrowth - S2-E2
Plot hole: While the girls are trying to work out who killed Jeremy, Rosemary says she thinks it's Julia - Julia owns the flat that Jeremy and Marcia live in - so Laura says "Why would she want Jeremy dead?" And Rosemary says "To sell the house for a greater amount of money." But that's wrong: When someone dies in a house, the house sells for less, not more - not many people want to live in a deceased estate.
Chosen answer: As far as hanging new wallpaper, there is no need to brush on any additional product once it has been pasted to the wall. It appears Helena may be doing an extra decorative step by applying a liquid glaze over the wallpaper to give it a more distinctive look, perhaps creating a sheen effect on the surface. Glaze can also be tinted to give a muted colored tone. It could also be a protective sealant. However, to remove old wallpaper, a product is brushed on that dissolves the old paste so the paper can be easily scraped off.
raywest ★