Grantchester star Kacey Ainsworth on the mental health storyline close to her heart

Grantchester Kacey Ainsworth

Cathy Keating is heartbroken...

Grantchester star Kacey Ainsworth tells us that her screen mum’s mental health storyline is based on her own grandmother’s real-life experience, ahead of tonight's final episode.

"My nana was a paranoid schizophrenic so I have first-hand experience of mental health issues," says Kacey, who as Geordie’s wife, Cathy Keating, has been heartbroken ever since screen mum, Diana (Paula Wilcox), was taken away for medical treatment in a psychiatric hospital.

"The producers and I had a chat about Diana coming into the family and they said they wanted to explore mental health. I told them about my nana, Nancy, who was diagnosed as schizophrenic at 72, after a lifetime of some appalling behaviour – not because she was a terrible person, but because she was mentally ill.

"That’s when we decided to make Diana bipolar, with paranoid delusions, and use some of my personal stories. It’s what Grantchester does so well. We shine a light on current topics – in this case, mental health issues – and look at how they were dealt with in the 1950s. Which for most people, involved keeping it a secret."

Cathy Keating is heartbroken about Diana in Grantchester

Cathy is very worried about Diana (Image credit: ITV)

Diana’s behaviour became increasingly erratic throughout the current fifth series. From arriving to help out in the house, she became manic - culminating in her throwing a disastrous dinner party which ended with her trying to do ‘home improvements’ on a wall using a mallet!

Quick to cover for her mother’s behaviour, Cathy’s initial reluctance to tell Geordie (Robson Green) that Diana’s bipolar, reflects the era’s fear surrounding mental illness, insists the former EastEnders star.

"You didn’t talk about it in those days, for fear your loved one would get carted off to a mental institution and never be seen again," says Kacey.

"Provision for any kind of mental health problems was appalling back then. Any mental issue – even post-natal depression – saw sufferers all treated in the same place, sometime drugged up with medication that turned them into zombies.

"So you kept it a secret within the family. Just like my mum and aunt kept Nana’s illness a secret because they didn’t want her taken to the nearby mental hospital."

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Grantchester Kacey Ainsworth as Cathy

(Image credit: ITV)

In one scene, Diana insists on taking her grandchildren out of school for a day out – which was based on a real-life incident Kacey had with her nana.

"She kidnapped from me from school once. I was on a school trip and she came to pick me up, insisting she was my grandmother and needed to take me.

"She took me back to her house and I remember knowing I shouldn’t be alone in a room with her, but not knowing what to do. The teachers rang my mum and the police had to come and get me in the end."

Kacey is, she says, proud of the way Grantchester deals with the darker side of life.

"Period dramas can be easily romanticised, all chocolate-box and lovely costumes, but we like to be a bit more thought-provoking than that. People respond to darker issues and I thought it was important to show that provision for mental health sufferers in the 1950s was pretty appalling."

Grantchester concludes tonight on ITV at 9pm (see our TV Guide for full listings).

Written by Rebecca Fletcher

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