I Am Ruth review: Kate Winslet is heartbreaking in powerful drama

So, now that you know that... this is seriously powerful stuff. I Am Ruth is the latest in Dominic Savage's I Am series, which since 2019 has been telling distinct, one-off, female-led stories using innovative, improvisational filmmaking techniques.

This is the series' first feature-length instalment, clocking in at around an hour and a half without adverts. It tells the story of Ruth, a working single mother, and Freya, her 17-year-old daughter.

As Freya becomes more subdued, distant and antagonistic towards her mother, Ruth begins to suspect that her daughter is developing an unhealthy obsession with social media, but feels powerless to help.

It will come as no surprise to anyone that Winslet is absolutely phenomenal here. Her Ruth is a deeply human, multi-faceted and flawed individual, who is easy to root for and empathise with, yet is refreshingly imperfect - she gets things wrong, sometimes disastrously so.

There are scenes in which she is utterly sympathetic, others in which her lack of delicacy, tact and understanding is infuriating, and some in which she is heartbreakingly vulnerable.

The fact that Winslet manages to take us across this gamut of complex human emotions within an hour and a half, while still feeling like a complete and consistent character, is a testament to her skill and craft, yet also to her dedication to this project. It's clear this has been something of a passion project for the actor, and her commitment bleeds through the screen.

The revelation here is Mia Threapleton. In truth, the idea of a famous actor's child appearing alongside them, in what is one of their earliest roles, is always going to be an unnerving prospect. It could go so badly wrong. But from the moment she appears on screen, Threapleton puts those fears to rest.

Just like her mother, Threapleton manages to thread the needle, making her character relatable and sympathetic, despite at times, particularly in early scenes, being exasperatingly obtuse. She is having to sell emotional states that her own character doesn't completely understand - a mammoth feat, yet one that she pulls off to remarkable effect.

Of course, Threapleton's strength as an actor was of crucial importance, because this really is a two-hander. Ruth may be granted slightly more of the overall focus, but what's so impressive about the film is the ease with which it shifts perspective between mother and daughter, almost imperceptibly.

From moment to moment you will find yourself agreeing with or identifying with one or the other, giving their inability to understand one another a sense of helpless inevitability.

The film is a masterclass of slow-build tension. While the first half-hour takes things at a steady pace, allowing only glimpses into the desperation beneath Freya's surface hostility, the drama then steadily descends into a stress-inducing nightmare. It's the sort of thing you feel compelled to look away from, fearing what is coming next, but unable to do so.

Knowing how this was created makes it all the more impressive. Improvisation can lead to aimlessness, but here it allows the quieter sequences time to breathe, the characters' frustrations time to build and it lends the performances a dose of authenticity.

The feature-length runtime also helps. One can imagine a truncated version of this story which lurches from one to 10 and releases its tension all too quickly, in order to fit a neat 45 minute time-slot. It might have been more palatable for audiences (again, this is a tough 90 minutes) but its impact certainly would have been lessened.

Aside from a couple of minor chuckles, usually from Winslet's dry, off-hand comments to herself, there isn't much levity to be found here. It's perhaps unsurprising given the subject matter, but it does make the watch gruelling at times.

It's not the sort of thing viewers will likely be coming back to time and again, more a one-off experience that you will likely come out of feeling drained. It's also sure to stay with you long after the credits role.

That, of course, was the purpose of this piece right from the start. Winslet has spoken about wanting to highlight issues around teenagers' use of social media, saying they are "so extraordinarily prevalent at the moment, and alarmingly so".

I would be surprised if I Am Ruth assuaged any parents' fears - aside from brief moments of hope, there is little in the way of resolution or catharsis here.

But it does contain some subtle, informative messages around how to seek help, and if it helps parents and teenagers alike to feel seen and understood, then it will have done its job.

Whatever the social implications, there's no doubt this is an impressive piece of British social-realist drama - and a stunning showcase for a real-life mother and daughter unafraid to be astoundingly vulnerable on screen.

For more information and support around mental health, please visit Mind's website or call its info line on 0300 123 3393.

I Am Ruth will air on Thursday 8th December at 9pm on Channel 4. Looking for something else to watch? Check out our TV Guide or Streaming Guide, or visit our Drama hub for more news and features.

The latest issue of Radio Times magazine is on sale now – subscribe now. For more from the biggest stars in TV, listen to the Radio Times View From My Sofa podcast.