As BBC One thriller The Control Room arrives on our screens, Danielle de Wolfe meets the cast alongside creator Nick Leather to discover more.

Dealing with life or death scenarios is all part of the job for Britain's emergency service call handlers. A role that requires a cool head and an even cooler phone manner, adrenaline comes at no extra cost.

It's something Bafta Award-winning screenwriter Nick Leather knows all too well, given his latest project - new three-part BBC thriller The Control Room - spawned from his own desperate 999 call for help. Stunned by the profoundly intense relationship he built over the course of several minutes, the anonymous voice at the other end of a phone became the premise underpinning his latest on-screen drama.

Describing call handlers as "everyday heroes", the screenwriter is far more accustomed to the buzz experienced by first responders when answering a cry for help. After all, recent years have seen him embedded with police units during high-octane drug raids and liaising with social services as part of his research for new heart-stopping storylines.

"I do have a bulletproof vest in the shed, obviously, because you need to keep these things handy," quips the writer with a smile.

"I was embedded in Greater Manchester Police and went on high speed car chases and drug raids and all these exciting things... I ended up in a situation where the detective was shouting at me: 'Put your bulletproof vest on'. I was like, 'Oh, no. I thought that was just there for show'."

Given his experiences, it stands to reason, then, that Leather's latest project - specifically set within an ambulance control room - should be equally as frenetic.

THE CAST

Led by Ian de Caestecker (Roadkill, Agents of S.H.I.E.L.D.) as call handler Gabe, the series finds him answering an incoming call for help - only to discover the distant voice at the other end of a phone appears to know him personally.

"Every few minutes, [Gabe] deals with matters of life and death. And then one day, he takes one call and realises that the life on the line is actually his own," explains Leather.

With chaos ensuing, the series sees de Caestecker joined by Joanna Vanderham (Crime, Warrior) as Gabe's new female acquaintance, Sam, with the pair challenging each other every step of the way.

Also starring Sharon Rooney (My Mad Fat Diary, Two Doors Down) as a police detective named Breck, the show explores what happens when Gabe, a man accustomed to helping others, finds himself on the wrong side of the law.

"From spending time in the police, what I was amazed with, [was] I thought a lot of the police I see on telly aren't quite right," says Leather.

"I needed to ground [Rooney's] character a lot and make her much more normal... She shouldn't be like a TV detective... The detectives I met, one of them was a travel agent until they became a detective. It's just grounding it and keeping all the characters as real as possible."

ROOTED IN REALITY

Describing call handlers as "ordinary people" dragged into "crazy" situations, 34-year-old de Caestecker says he felt a "degree of responsibility" when it came to portraying the career accurately on-screen.

"I went in and spent a bunch of time in real life control rooms - you could say they're kind of the invisible side of the emergency service," says de Caestecker. "They're faceless, really, but they do such an amazing job, and I guess, potentially, they don't get the credit they deserve. So, that was one thing we were very conscious of, just making sure that we did that respectfully."

A tale that came about after Leather was forced to call 999 for the first time, the dramatic events that unfolded soon blossomed into a brand new on-screen concept.

"I went to wake my youngest daughter up - she was only very little, and we couldn't wake her in the morning," recalls Leather. "Her eyes were half open, and we couldn't wake her. It was that horrible thing where you suddenly start panicking."

Noting that his daughter turned out to be "absolutely fine", Leather says that when searching for new material, he regularly found himself reflecting on that fateful day.

"Just for a few minutes, when you don't know things are gonna be alright and you're so desperate, it's such an intense conversation with someone you don't know - you never spoke to before, you're never gonna speak to again, you don't know what they look like and they don't know what you look like," says Leather.

He adds: "I just thought: what if an emergency call room handler was pulled into the emergency? What if, in that professional situation, suddenly it was a personal situation?"

A JOURNEY OF DISCOVERY

With Gabe "stuck in the past" according to de Caestecker, and Vanderham noting her character Sam is "lying to herself", the pair act as mirrors held up to one another. It spawns the realisation that they've "been blinkered for 20 years" according to the actress. Yet, in spite of the chaos, the pair's journey is every inch a tale of positive self-growth and rediscovery.

"I think it focuses on the fact they've been living these lives they feel are on a set path. And it isn't until they meet as adults, that they realise they've got choices and they can make changes," says Vanderham, 30.

Describing how Sam "coming in like a whirlwind" shakes up Gabe's view of the world, the pair's ensuing adventure - described by Vanderham as "absolute chaos" - leads to the duo swapping the mundane for the mysterious.

"Sometimes, when you're watching a thriller, I think your hero loves being in a thriller a bit too much," smiles Leather.

"And so, I thought my hero should be someone who doesn't want to be in a thriller. It's his worst nightmare. He wants to be in a rom-com. Gabe has stumbled into the wrong show... he doesn't want to have taken that call."

The Control Room arrives on BBC1, tonight at 9pm