Kieran, a paramedic who works long and unsociable hours, and Gemma, who runs the coffee shop on the street outside their home, are struggling to find time for one another. The daily grind is getting grinding, and it doesn’t help that they live in one of the most expensive and busy cities in the world – London.

“The time you meet her and Kieran is so gorgeous, because they are missing each other, and love is so envious and exhausted and lustful and frustrated when you’re missing someone,” says Teixeira. They’re like ships that pass in the night (or the morning), so much so that in a scene that’s both incredibly sad and tender, they steal a “date”, which involves walking one quick loop around their cramped apartment together.

As Kieran (Gary Carr) wishes Gemma (Thalissa Teixeira) “good morning”, she tells him “goodnight”.
 

The cash-strapped couple are finding it difficult to make their mortgage payments, so in comes the solution… Ray. She’s a 30-year-old Olympic synchronised swimmer, but an accident forces her into early retirement. “She doesn’t know it, but she’s ready to fall in love,” says Labed.

As the friendships develop, Ray is simultaneously there for Gemma and Kieran when they can’t be there for each other, almost acting as a buffer to their combined stresses. Teixeira explains, “When Ray shows up, there is time in the no time.”

Ariane Labed actually trained in synchronised swimming for her role as Ray.
 

Athina Rachel Tsangari (Attenberg), who is best known for working in film, was brought on board to direct for her first television series, which, at its core, she says, is about “humans trying to survive in a contemporary city”. Gemma, Kieran and Ray’s house-sharing situation is not uncommon, and neither is the fact that they all come from different backgrounds. That’s just London – and one of the most beautiful aspects of the city at that.

Tsangari mentions that “maybe” Gemma is from Brazil, but it’s never part of the storyline. Similarly, Labed, who has been living in London for eight years, is French in real life and in the show. “I love the fact that there is absolutely no prejudice. It’s just normal, the same way they fall in love – almost like gender blindness,” Tsangari says. “They just can’t help but fall in love, because they fall in love with each other’s humanity.”

“It’s really beautiful. She’s gonna make me cry,” Labed interjects, patting at her eyes. Listening to Tsangari speak and being in the same room with her and the cast, it’s clear that there is such a strong bond and an established trust between them. It translates ridiculously well on screen, with every lingering glance, subtle touch, thoughtful gesture and non-verbal form of communication resonating.

The cast, plus director Athina Rachel Tsangari, makes it a foursome.
 

Their believable longing for one another, and their uncertainty about what they should or shouldn’t do, is deeply moving, and Tsangari says it’s down to the cast and creative team’s “choreography” on and off camera. “We did cast for this human chemistry. Everyone was part of this very gracious team, dancing around our amazing actors and supporting them”. “She’s gonna make me cry again!” Labed laughs.

Before shooting, the actors were given a week of rehearsal time, which allowed them to connect with their parts and each other. Without giving too much away, obviously things get intimate between their characters.

Throuples that brush their teeth together stay together.
 

While you might have a notion in your head of a show about polyamory being focused on sex, it’s not the case in Trigonometry. “It was not written this way about being a sexy show. It was always going to be a human show. The sexual thing is all about [an] exchange of tenderness and of fears and of inhibited desire that tries to be liberated,” says Tsangari.

The actors were offered an intimacy coach on set as a way of ensuring everyone felt comfortable during those scenes, but they declined. Carr says, “I’ve been on shows where an intimacy coach was definitely needed. But we built such a rapport between us that there was a lot of trust and respect. And if any of us felt like there wasn’t, we could have had that conversation. It felt very easy.”

Paramedic Kieran really is a hero. “All these toxic masculinity things you usually see on screen with [male] characters didn’t apply to Kieran,” says Carr.
 

So how does the number three sound now? Well, the arrangement seems to be suiting our throuple – for now. During a night out with Gemma and Kieran, a drag queen asks Ray who the “unicorn” (a person invited into an existing couple) is among them, going on to say that “it’s the third party who makes it a party”. But only time will tell whether “three’s a crowd”. Trigonometry is pretty difficult, after all, and in this case, there are three sides to every story – and every triangle.

When is BBC Two’s Trigonometry on TV?

Trigonometry airs on on BBC Two HD (CH 102) on Sundays at 10pm, with the first episode screening on March 15th. It is also available for 30 days in Catch Up > Channels > BBC iPlayer. 

The eight-part series will subsequently air every week until Sunday 3rd May.