Good Omens star Michael Sheen joins award-winning BBC Radio 4 ...

When Ashby and Taylor discover a box of unseen evidence from a deceased witness, they soon find themselves uncovering the terrifying legacy that PCB chemicals are having on the environment, our food chain and our communities.

And, in an unexpected twist, the podcast hosts discover that actor Michael Sheen recorded the witness’s final testimony.

Buried: The Last Witness will "reveal the results of a one-year investigation involving dossiers of evidence, unseen documents and exclusive testing of British soil, supermarket food and even human blood," according to the BBC.

Ashby said: "Most true-crime series have a victim, who we all feel empathy for. But in this one, we know the poison, we know the culprits, but the scary question is this: are we all the victims? I've never recorded an investigation that is at once so universal, and so deeply personal."

Taylor added: "Every day, sometimes every hour, we have obsessed over the life of one man. He was brilliant, polymathic and eccentric. He is the most unlikely environmental hero.

"But who really was he, and what did he see? Could that one field, in 1967, change all of our lives? Once you see what he saw, Buried: The Last Witness becomes necessary listening."

Sheen said: "It's hard to get your head around. This story is about the first of the forever chemicals. And there are so many of them since then. We want people to understand what they are doing right now."

Buried: The Last Witness will be broadcast weekly on BBC Radio 4 from 24 June. It will also be available as a box set on BBC Sounds.

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