Grantchester's Kacey Ainsworth explains why female-centric episode tackles rare issues for period drama

"Trying to get by in a world that isn't made for us, that's cold and brutal," she added. "And now you know Esme is old enough to see it too.

"And just like you did when she was swimming, you moved your hand away and told her how well she was doing. You let her go."

For what other option is there?

It was Kacey Ainsworth who penned this particular episode, which also marks her writing debut.

The actor had "suggested lots of ideas for Cathy's character and for the show over the years", she told RadioTimes.com, with "some of those ideas being taken up and put in the show".

"Then I suddenly thought: 'Why don't I have a go at writing one?'" she added.

Immediately, Ainsworth knew "it would be about some of the female issues that don't normally get covered in period drama".

"I just think it's very interesting to look at where we are now, and then to look at how things were for women then in terms of things that... are of media interest at the moment, such as menopause [which is set to feature in a later episode], sexual harassment at work, women's place in the workplace.

"And I just wanted to show how difficult it was then, but also the fact that in quite a lot of period dramas, you only ever see women in domestic settings. You never see them at work. You never see them doing those kinds of things.

"I wanted to show that it's not just in the last 20 years that women have wanted to crack the corporate ceiling... like the fact that Miss Scott was not allowed to be a police officer at the time, like the fact that women couldn't get a loan for a business or couldn't get a loan for anything until 1988, unless they had a man to back them up."

Over the course of the episode, we see the toll that sexism and misogyny take on the women of Grantchester, the most overt example being the murder of Mae, a young woman who worked as a secretary alongside Esme.

Initially, the police suspected that the cause of death could be a tragic but unfortunate accident, but it quickly emerged that there was something much more sinister at play.

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Mae was not the first female employee at Harrison and Sons to have suffered an untimely demise. In fact, she was one of many.

From carbon monoxide poisoning to a botched abortion, the numbers had gradually ticked upwards over the years, the latest explained as easily as the last, as life in the office continued as normal.

Nothing to worry about. Nothing to see here.

But on closer inspection, a privilege the previous victims weren't afforded, the reason for their deaths began to take shape, the shape of an 'M', to be precise.

Malcolm, a senior member of the team who was destined to step into the boss's shoes, had been exploiting his power for sexual gain by taking advantage of the newer female members of the team – that is until they fell pregnant, after which they were of no use or interest to him.

Ms Cheadle, the office manager and loyal servant to boss Mr Harrison, herself a victim of the patriarchy, would then orchestrate their demise, which would be filed on a company account sheet under 'cleaning', the victims cruelly reduced to a footnote.

And so the cycle continued, the micro feeding into the macro as wolf whistles and leering looks turned into dangerous, sometimes fatal liaisons.

And despite recent developments, that looks set to continue, even though Ms Cheadle was arrested for her crimes.

Malcolm, while morally bankrupt, didn't break any laws. His finger prints weren't on the bottle of almond extract used to contaminate Mae's birthday cake and cause a fatal allergic reaction.

That was all Ms Cheadle's doing, who had dedicated her life to picking up after men, in both mundane and extreme ways, and would now spend the rest of her days behind bars while the likes of Malcolm faced no real consequences for his actions.

When put in such blunt terms, it's no wonder Cathy has been so concerned for her daughter's wellbeing as she enters womanhood.

"She's worried about Esme, but it doesn't necessarily come out in the right way because she hasn't got the terminology for it," said Ainsworth of the increasingly heated altercations between the pair.

"It's about those feelings that we've all had, when we've been in a situation that feels a little strange, or a little odd, or there's banter that you don't like.

"It's really difficult, even now, for us to voice saying, 'I don't like this.' Because you get called names, you get called a diva, you get called precious, making things difficult.

"We still have that now."

Grantchester season 9 continues on Wednesday at 9pm on ITV1.

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