Jean wears a silver counter around her wrist. If she says more than 100 words in one day it issues an electric shock. She's stopped meeting friends for drinks, no longer talks to her husband and can't read her daughter bedtime stories. The average person uses about 16,000 words a day, often without really thinking about what they are saying. So what would happen if that right was taken away from half of the population?
That is the premise of Christina Dalcher's debut novel, Vox, about a dystopian world where women's daily speech is restricted to 100 words - the length of this paragraph.
"I wrote Vox as a cautionary tale about gender politics, backlash and cultural shift," says Dalcher, a 50-year-old American who has a doctorate in theoretical linguistics and only started writing novels four years ago.
It's gone well. Sarah Jessica Parker called Vox "a great summer read by a special female voice" and there are talks about adapting it for film.
Dalcher would like Ashley Judd or Charlize Theron to play Jean, a woman who has been forced by the state to give up her fulfilling and prestigious job as a scientist working, ironically, on curing language loss, in order to look after her children.
It has been read as a reaction to Donald Trump's America, but it's broader than that.
"I am against any kind of authoritarianism," says Dalcher. "That goes for every side of the political spectrum. It has very little to do with the current president; it's more to do with government control in a general sense. We see this hushing up of people coming from both sides - look at university campuses."
Her novel has been compared to Margaret Atwood's The Handmaid's Tale. Both are set in a society where motherhood and purity are fetishised.
Why does Dalcher think dystopia is so popular at the moment? "I'm a Stephen King-a-holic. I've been reading him since I was 13. In his introduction to Danse Macabre he talks about that sense that we have enough horrors in this world so it's sometimes pleasant to escape them. They remind us that the world as we know it is not as scary as we think - it could be a lot worse.
"If ever I'm stressed, I tell my husband I'm going to watch a soothing horror movie and it relaxes me because the stories can be so 'out there' that they take us to a darker, alternate world that can be a warning. With Jean and the wrist bracelet there's an element of 'Hey, don't let that happen to you'."
Time magazine called Vox a novel for the #MeToo era. Dalcher wasn't thinking of that when she started it in May 2017 - indeed, the #MeToo movement hadn't started yet.
"But Vox is related to women banding together so it's timely," she says. "I had a backlash in mind when I was writing - women began to be so vocal in 2017; we had a lot of marches, a million women showing up in Washington DC, so it was on my mind that there would be some faction that would react by saying 'Enough, we don't want to hear you any more'.
"These bracelets get snapped on women partly because of a diabolical fundamentalist movement that wants to return to a culture of domesticity, which was a real thing in the UK in the Victorian times and the US."
Does she, like Jean, feel silenced and as though she needs to rebel? "Absolutely. Every single day - about politics, religion. Sometimes it's not like people are actually silencing me but there is pressure to censor yourself to not cause any hurt. I wonder if there's anyone in the world who speaks with absolute frankness."
She would like to address another taboo. "I noticed something a while back," she says, tentatively at first. "Without getting too personal, a lot of women who suffer miscarriages or infertility never talk about it. On Mother's Day everyone is very effusive on social media.
"I always tweet a gentle reminder that not everyone has children and it's not a choice for some people.
"When people ask if you have children, they are expecting you to say, yes, they're so lovely, la la la or," she switches into an emotionless voice. "'No'. Women as a rule don't say, 'I don't have children; I had miscarriages'. Or 'I wanted to and I couldn't'. Or even, 'I don't like children'.
"It's important that we look at a different type of silence. If you are having a casual conversation with someone you don't know there's that fear that if you say you've had an abortion they will come back and say 'I'm pro-life'. Or not know what to say if you've told them you've had a miscarriage." She is unfazed, though, about the moves in the US by far-right republicans and the Vice President to repeal the 1973 Roe vs Wade ruling that legalised abortion.
"People have been concerned for some 40 years about this - there is precedent. I can't say there's more fear now than 20 years ago," she says.
Is Trump popular where she lives? "You can't get elected if you aren't popular. We have these different factions and the more distant people get from one another the harder it is to communicate."
The safe space culture at universities concerns her. "They are driven by fear and intolerance, which feed off each other. One reason I wrote Vox is I have a terrible fear of control. If we look at our past and present, it seems like there's always some effort by one group to control another.
"With respect to intolerance, maybe some people have such strong feelings that they can't tolerate anyone different or are making us speak in a different way to control us."
There is "a whole other novel" in her "about the frightening ease with which we can misunderstand each other or fail to get our own points across in a civil way, particularly with social media platforms that constrain the number of words we use".
She adds: "We have to take responsibility for what we speak up about: read the whole newspaper story, not just the headline. There's a responsibility that comes with free speech."
Dalcher grew up in New Jersey. Her father was in the furniture business, and her mother looked after Dalcher and her younger sister and brother, "shuffling us off to ballet lessons".
She lived in Clerkenwell from 2006 to 2009, researching speech patterns around the letter 'R' at City University. She still calls cigarettes 'fags' (she's desperate for one).
After that she and her husband Bruce, a maritime attorney - "I call him a boat lawyer, which isn't accurate but it's cute" - spent three years in Abu Dhabi, then several months in Sri Lanka "just hanging out".
The book is dedicated to Bruce, "who never, ever, tells me not to talk so much". He's the first person she shows her work to.
She started writing six months after returning to the US after being abroad for seven years.
"I had reverse culture shock. My academic career was a bit" - she gestures downwards - "on the way out because I hadn't done very much with it. One night I woke up, nudged my husband and said people write books all the time. Stephenie Meyer was 29 when she wrote that Twilight book - what's stopping me? I'm going to write a book. This was three in the morning so my husband was like 'Yeah, honey, we are going to talk about this tomorrow'." She got up and started drafting an idea.
Vox was written in two months. "You can't write a book that quickly if you're not good at focusing. I can shut out pretty much the entire world. I try to write a few thousand words a day, finish up early afternoon and do something fun."
She has never limited her speech as in the book but has known days of silence. "My husband took a part-time job in the Middle East when we were in the UK, so every two weeks I was alone. We'd just moved to Hertfordshire, where I didn't know anyone and there were a few days where I didn't talk to anyone. It's debilitating, demoralising," she says.
"In military training they teach that it's important to keep up communication even if it's just in tapping code because when you lose that bridge with other humans something disastrous happens to us inside."
She's already written a second book that draws on similar themes to Vox. "It has the same near-future dystopian elements, resembling our own society but with a twist. I'm looking at the mania for exaggerated intelligence."
But the ideas of Vox endure. "Freedom of speech is more than simply getting your point across. It's making sure you are saying the right thing."
Vox is published by HQ on August 23 EVENING STANDARD ©
Statistically, it's easier to be consistently funny and intelligent if you say less. Occasionally, I'm jealous of those friends who don't say much but when they do decide to pipe up they have something worthwhile to say. I'm the opposite, articulating my thoughts without thinking, idly hoping that at least some of them weren't fatuous.
So, at first, not being able to speak is as debilitating as I feared. I've warned my loved ones that this was coming and I'm not being rude. My friends tease me the day before by silencing me every time I open my mouth.
"This is coming out of your allowance so it had better be good," they mock. I glower, practising at communicating with a dark look instead of words. They ask if I'm feeling okay because I look so odd.
Non-verbal cues become important. I try to give my boyfriend a meaningful good-morning smile but he just laughs at me (no, not with me). On an outing to buy milk I'm torn: not thanking the man at the checkout feels rude but it's also a waste of a word - obvs I'd say "thanks" instead of "thank you" (I'm no amateur). I pretend I have laryngitis, gesturing to show I've lost my voice.
Reading and writing are verboten too (that's why I'm doing this at the weekend - it wouldn't be feasible at work). It's refreshing to have an excuse not to check e-mails and break from the noise of Twitter. I delude myself that looking at a constant feed of news (Instagram) keeps me informed but when I come to catch up the next day I haven't missed anything and find I concentrate properly reading whole articles, thereby being more on the pulse than had I spent a day exhausting the zeitgeist.
At a lunch with friends that I couldn't cancel I worried that people would tire of the mute in the corner but actually they enjoyed having a captive audience. If you can't talk back, you hear more. And you notice other things. I slowed down to eat, really tasting my food rather than shovelling it in between trying to keep up with the conversation. However delicious my pizza was, though, it was annoying not being able to join in, especially when I had a great anecdote to contribute to the conversation. I told myself it would hold but knew it wouldn't. I can't imagine having to be silent in my open-plan office either.
At the end of the day I assumed I would be a better person, one for whom every word mattered. Instead, I blurted out a jumble of observations that I didn't realise had been building up all day. And then I had a glass of wine and said thank you.
I am a social animal and I have no desire to do it again.