The Chernobyl miners faced certain death to dig a tunnel. In the end, they didn't need to.

In the early morning hours of April 26, 1986, the Chernobyl Power Plant in the Ukraine exploded in an unprecedented nuclear disaster.

Instantly, two men were killed in the blast.

In the weeks that followed, more than 100 people, the majority firefighters who were first on the scene, developed acute radiation syndrome.

In just a few months, 29 of them had died.

You can watch the official trailer for Chernobyl, right here. Post continues after video.

The first responders at the scene were just the first of the victims of Chernobyl – a disaster which would have a lasting impact for decades to come.

In the days that followed the nuclear disaster, more than 68,000 people were evacuated from a 30 kilometre radius while thousands of men began the mammoth effort of cleaning up the toxic mess the explosion left behind.

In critically-acclaimed new HBO series, Chernobyl, the aftermath of the disaster is recounted in great detail, when thousands of miners, firefighters and recovery operation workers were forced to work in incredibly toxic and dangerous conditions for the sake of the greater good.

During the third episode of the series, Valery Legasov (played by Jared Harris) has to convince a group of over 400 miners to work in extreme levels of radiation in a bid to protect millions of civilians.

At the time, it was feared that the nuclear power plant’s melted uranium could sink into the Earth and infect the Black Sea, contaminating the water supply of millions. As a result, the miners were required to build a tunnel underneath the core of Reactor Number 4 to prevent the major water source from becoming contaminated.

But while the miners were exposed to fatal doses of radiation for days on end, the true horror of the Chernobyl miners' story wasn't revealed until years later.

Despite their belief that digging the tunnel was essential to the safety of greater Europe, the miners later learned that the tunnel they risked their lives to build was never necessary. In the end, the uranium didn't even melt through the concrete beneath it, meaning that it had no way of reaching the Earth or the Black Sea.

Regardless, Legasov had no choice but to order the tunnel be built. The threat was too high to reconsider.

“It’s just a chilling fact,” Craig Mazin explained on The Chernobyl Podcast.

“I would put myself in Legasav’s shoes there and you start to realise the cruelty of the situation. You have no choice. A 50/50 chance that you’re going to poison the Black Sea forever is not acceptable.”

During their work, the miners were exposed to radiation levels to the equivalent of anywhere between 80,000 and 160,000 chest X-rays, according to the World Health Organisation.

Although the death toll from Chernobyl is still unknown, it's believed approximately one out of four of the Chernobyl miners later died as a result of radiation poisoning, with many dying from cancer.

"They were tough. And they chose willingly to [build these tunnels] in part because of a general sense of honor and community," Mazin said.

The five-part miniseries Chernobyl is available to watch now on Foxtel. 

For more on this topic:

• Running behind buses, howling for their owners: The Chernobyl pets who were left behind.
• The harrowing true story of Chernobyl's Vasily Ignatenko and his pregnant wife Lyudmilla.
• The Chernobyl nuclear disaster was the worst in history. Here are 4 things you didn't know.
• Chernobyl is the gripping new HBO drama people are rating higher than Game of Thrones.
• Exactly how to watch the Chernobyl TV series online in Australia.