In July 2024 a startling scientific paper was published.

Headlined ‘Evidence of dark oxygen production at the abyssal seafloor’, scientists told how they had discovered oxygen being made two and a half miles down, at the bottom of the Pacific Ocean.

Their claim centred on small polymetallic nodules on the seafloor, and the key question - could these lumps of metal somehow be making oxygen in complete darkness?

It was an extraordinary finding that, if proven, could overturn hundreds of years of scientific knowledge about how this crucial ingredient for life is made. It prompted global headlines and split scientists.

But a year and a half on, are we any closer to knowing the answer... Is dark oxygen really possible?

BBC News science correspondent Victoria Gill investigates for BBC Radio 4, and finds so much more than a scientific anomaly.

Dark Breath is the story of a scientific controversy played out in real time. A row about science that became personal. And a discovery that crashed headlong into the debate about whether we should mine metals from the deep sea.

What does the story tell us about the messy and human scientific process? And what bearing does it have on the decision to exploit some of the last untouched parts of our planet?

Presenter: Victoria Gill Producer: Gerry Holt Editor: Ilan Goodman