For eleven years, Tony Schumacher patrolled the streets of Liverpool as a first responder, witnessing the results of horror crimes, people pushed to their limits and communities destroyed.
So harrowing was his experience, he eventually had a nervous breakdown and became homeless.
He says he saw "good, hardworking people being stretched beyond belief" while working on the frontline, and pointed out being a responder means you are never the person to give good news.
Instead, you're "somebody who kicks in doors, races around town centres and who fights literal and sometimes metaphorical fires".
Tony told the Liverpool Echo : "When I first joined the police, I remember on my second or third night, an old bobby called Colin said to me ‘you will never knock on someone’s door and tell them they’ve won the lottery’.
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"You are only ever going to deliver bad news in this job; so it’s a big responsibility to take on but conversely, it’s incredibly exciting.
"Occasionally, you do things that change people's lives be it saving someone’s life or locking up a criminal – you and your colleagues are working all night, every night and living constantly on your wits."
In 2006, Tony said he "cracked up" and could no longer cope with the pressure and trauma of the job.
After a period of homelessness, he then became a taxi driver.
Inspired by his experiences and keen to share them, Tony turned his hand to writing and became a highly successful author with his first novel The Darkest Hour, an alternate history set in a 1940s UK after a German Victory in World War II.
"My dream when I was a kid was always to be a writer even though I really was the thickest kid," he said.
"But when you’ve got nothing, you’ve got nothing left to lose."
After that, he self-published Rear View Mirror: Stories from the streets and the night - a recounting of his tales from his former life as a police officer and taxi driver, along with two more novels.
Tony was then lucky enough to be mentored by screenwriter Jimmy McGovern, responsible for popular shows including Time, Hillsborough and Cracker, through a TV writers' bursary scheme.
During a trip to the pub with Jimmy, Tony came up with the idea of turning his experiences into a screenplay.
It was there that The Responder was born, and on Monday night the finished masterpiece will air on BBC One, with The Hobbit star Martin Freeman playing the main character, who is based on Tony.
"I really felt the need to get across the pressure people are under," said Tony.
"It was like working on a piano wire, we were stretched so thin. People are really, really struggling to do their jobs, but they've got no choice."
He added: "It wasn't always doom and gloom, you have to see the funny side to things, there has to be humour.
"And I don't think we could've made a show based in Liverpool without comedy."
Martin plays Chris Carson, an unconventional officer who works a series of night shifts, battling to keep it together both personally and professionally alongside his rookie partner Rachel (Adelayo Adedayo).
The show aims to "hold up a mirror up to the emotional, heartbreaking extremes of modern day policing".
To prepare, Martin said he spoke to himself in the Scouse accent for 18 months beforehand.
"I walked around for a year and a half, occasionally just talking to myself in Scouse," he told the Metro.
"Even though you're not always the best judge of your own thing, I do trust my ear.
"If I say something, I know when it sounds off. I got very, very exact about that stuff. You have to be, because if I don't do it well, it's a terrible accent to get wrong."
* The Responder airs on Monday 24 January at 9pm on BBC One, with the second episode available to watch on Tuesday. The final three episodes will air on Monday, Tuesday and Wednesday next week. All five episodes will also be available to watch on BBC iPlayer after the first episode airs.
