The actress, who is set to play the titular character in the ITV drama, admitted there were many harrowing moments in the show and had to get herself into the right "headspace" before filming.
Chatting to HELLO! and other press in a Q&A for the series, the Downton Abbey star began: "When I've got do scenes that are very emotional, of which there are many, it is a sort of apprehension that sits with you like the day before or the day of."
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She continued: "It's partly the apprehension of having to get yourself into that emotional headspace, and partly like 'Oh am I going to be able to get there today?' and all of that stuff. So in certain scenes I have to just really concentrate and I think everyone knows when I put my ear pods in, that's my zone I just listen to music if I've got to do really emotional stuff."
"Purely just cause it helps me concentrate, I don't listen to anything specific that makes me sad, but it just stops me listening to the banter on set or getting involved in the joke."
Angela Black is released next month
Angela Black, which is due for release in October, is a psychological thriller from the writers behind Liar. Joanne plays the titular character, a suburban housewife who is hiding some dark secrets.
The official synopsis for the drama reads: "Angela Black's life appears idyllic: a lovely house in suburban London, days working as a volunteer at the dogs' home, two wonderful sons and a charismatic, hard-working husband, Olivier. However, beneath this façade of charmed domesticity, Angela is also the victim of domestic abuse.
"Trapped in a relationship she cannot escape, Angela is approached out of the blue by Ed, a private investigator, who spills Olivier's darkest secrets. When faced with some horrifying truths about her husband, a stunned Angela is left reeling. Can she really trust Ed? Can she leave behind her life as she knows it and finally free herself from Olivier?"
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