Episode 1

For years, Welsh actor Michael Sheen has been haunted by a story he discovered online about little-known farming consultant Douglas Gowan, who claimed the people of Wales had been poisoned by decades of toxic chemical dumping.

Douglas claimed thousands of tonnes of polychlorinated biphenyls (PCBs) - a known class 1 carcinogen often called the 'godfather of forever chemicals' - were dumped across Wales. Newport was a major PCB production hub for US chemical firm Monsanto and close to where Michael grew up. Michael read that Douglas spent 50 years trying to warn people about chemical dumping, but seemingly, no-one would listen. Unable to let the story go, Michael tracked Douglas down and interviewed him shortly before his death. Douglas described a lifetime battling corporations, claiming Monsanto knowingly buried highly toxic waste in communities with consequences still felt today. Determined to find out if Douglas was right, Michael embarks on a personal journey into alleged conspiracy and cover-ups.

Teaming up with environmental journalists Dan Ashby and Lucy Taylor, Michael digs into Douglas's archive of evidence. His research starts at Brofiscin Quarry near Cardiff, where in 1967, Douglas was called out to investigate livestock born with severe deformities. Visiting the area, Michael meets residents who played near the quarry as children, one of whom later discovered elevated PCB levels in his body.

Michael then visits Ty Llwyd quarry, used by Monsanto as a dump site between 1969 and 1972, where locals fear PCBs are still leaching into nearby woodland and linked a cluster of dog cancers to the legacy.
Seeking answers, Michael flies to Anniston, Alabama, home to another major Monsanto PCB factory. In an unprecedented move, the residents of Anniston took Monsanto to court for contaminating the area with chemical waste. Michael meets campaigner Dave Baker, who lost his teenage brother to a brain tumour after swimming in a creek contaminated by PCBs, and attorney Donald Stewart, who reveals documents showing Monsanto officials knew the hazards of PCBs as early as the 1940s yet continued producing and dumping them locally until 1972. The town fought back, securing a landmark victory and over $700 million in damages.

Meanwhile, Dan and Lucy discover that when production of PCBs ceased in Anniston in 1972, Monsanto actually increased production of the toxic chemicals in Newport.

Returning home, Michael works with forensic scientist Dr Dave Megson at Manchester Metropolitan University to test public land and farmland near historic Monsanto dump sites. The results are alarming: 13 of the 14 sites tested contain elevated PCB levels.

Land near two former sites in Wales show concentrations over 100 times the national background level, while a farm in Cheshire bordering a former dump shows PCB levels nearly 2,000 times the UK average. The farm belongs to Paul and Wendy, whose father died of blood cancer after years of potential PCB exposure. Despite taking their concerns to Parliament, the adjacent dump site was never cleaned up. Michael is left asking: how many other families have spent years trying to be heard, fearing for their health? He’s determined to find out and widens his research.