The shattered remains of Chernobyl’s reactor 4 are one of the most inhospitable places on Earth. Not only are the ruins physically dangerous, but they are highly irradiated, pitch black and shrouded by a crumbling, concrete sarcophagus, which is, in turn, covered by the New Safe Confinement structure.

But it is vital that scientists understand what is going on inside. And that task falls to Anatoly Doroshenko, a young scientist at the Institute for Safety Problems of Nuclear Power Plants (ISPNPP). He has what could be considered to be the most dangerous job on the planet: crawling deep within the ruins of the reactor to take readings and samples, getting within 8 metres of the core, sometimes as often as once a month.