She said that having studied Macbeth at school she felt she had a pretty good idea what the play was supposed to be like and was therefore initially sceptical about director Lloyd's post-apocalyptic vision for the production.
Asked about having to learn the Scottish accent she said having the Scottish cast around her helped and they were kind to her about pronunciation. She's gone for a softer accent compared to the others. Best compliment was her brother saying she didn't sound like Mrs Doubtfire.
On Lady Macbeth she says that she believes no one is totally evil and that she thought about part a lot before going for the audition.
"There is a tendency to assume that ambition is for her but she never says she wants to be Queen."
Wilson asked about the strong implications in this production that Lady Macbeth has lost a baby or that there is an absence of children (in the production James McAvoy's Macbeth touches her stomach when they meet up for the first time after the battle).
"She believes it can heal their relationships - it's grim that they do it [have a moment of tenderness] over a dead body."
Wilson observed its physically demanding for James and asked Foy if it is emotionally demanding for her. She said that Lady Macbeth has got the easiest task in that everyone else is running around, climbing up and down ladders and she wanders in reading a letter. She thought she'd be able to rein in the emotion but discovered quickly that you can't, the play sucks her in and carries her along.
Being the Scottish play the question of superstition came up and Foy promptly said "Macbeth" several times to prove she isn't said none of the cast are.
"People have fallen off ladders and hurt themselves if it's cursed it's already cursed."
Pre-theatre routine involves taking the time to make sure she's "looked everyone in the eye before you see them on stage" and "putting the dirt on". Then it's quiet time, pacing backstage and thinking about what she is going to do, while the opening scenes take place.
Macbeth runs at the Trafalgar Studios until April 27. and you can listen to tonight's episode of Front Row on the Radio 4 website. All Front Row episodes are also available to download as podcasts from iTunes.