Online videos of crazed deer crashing through the American countryside are racking up views online. They have the deer version of BSE – Chronic Wasting Disease, or CWD - and it's now spread to northern Europe too. Scientists are worried.

History repeats itself as hunters speculate on the origin theories of this deer prion disease. The US government insists people are safe, but conspiracy theories about a hoax or cover up are starting to spread online.

Written, presented and produced by Lucy Proctor

Did mad cow disease actually come from humans? Alan Colchester, the doctor who raised suspicions about the Kent meat rendering plant, has one of the most disturbing theories so far.

He publishes an academic paper that suggests a grisly international trade in decomposing animal remains could have brought the disease to the UK, after human bones picked out of the Ganges in India is unknowingly mixed with the cargo.

Will there ever be an answer to the origin of BSE? Scientist John Collinge is still looking.

Written, presented and produced by Lucy Proctor

Organic farmer Mark Purdey’s followers roll their concerns about pesticides into the public inquiry into BSE. A group of farmers who claim they were poisoned by pesticides join forces with green activists and work to get their own fears about neurological disorders in rural Britain onto the news agenda.

They fail to convince government scientists that pesticides are to blame for BSE, but their trust in mainstream science is destroyed forever – then Covid hits.

Written, presented and produced by Lucy Proctor

The BSE crisis becomes a lightning rod for other safety issues in the countryside. Organic farmer Mark Purdey becomes convinced pesticides are to blame for making cows go mad, and thinks they caused vCJD in humans too.

He sets out to prove his claims by crowd-funding for lab experiments. He becomes the star of the alternative mad cow disease community, for people who refuse to believe the official government narrative on BSE – or any other official narrative, for that matter.

Written, presented and produced by Lucy Proctor.

Mother Christine Lord becomes obsessed with the now infamous episode of agriculture minister John Gummer feeding his daughter a beef burger on TV in 1990. She wants to know what killed her son - and beef is the prime suspect. But as she investigates, she finds all is not as it seems.

Three decades on from the incident, John Gummer casts doubt on the widely-believed story that infected beef is what caused vCJD in humans.

Written, presented and produced by Lucy Proctor

The truth finally comes out, as the government confirms a new brain disease affecting humans. In late 1995 eminent neurologist John Collinge is brought onto the government advisory panel on BSE. Cases of a new brain disease in humans are confirmed - and it looks the same as BSE in cows. Then the crisis hits.

John Collinge is brought into an underground situation room where the government and its scientific advisors are trying to work out what to tell the public. Everyone involved up to this point has to account for their actions.

Written, presented and produced by Lucy Proctor.

Christine Lord lost her son Andrew to the human form of BSE - vCJD - in 2007. He was 24 years old. Christine compiles a list of culprits, she says are responsible for Andrew’s death, and publishes them on her website - home to her one-woman campaign to get to the bottom of who knew what about BSE. Among the names on the list is Sir Richard Packer, Permanent Secretary at the Ministry of Agriculture during the BSE crisis.

Soon after taking up his post in 1993, Sir Richard starts to worry. Concerning stories are coming out of slaughterhouses, as potentially infected processed meat is still getting into the human food chain - after pet food companies decided it wasn’t fit for consumption. Sir Richard denies any culpability for Britain’s BSE deaths – and says he did his job at the time. What was going on inside the Ministry in the early 90s? And who, if anyone, is to blame for what happened?

Written, presented and produced by Lucy Proctor.

Dissident researchers are convinced the scientific establishment is wrong on BSE, and one microbiologist is convinced a major human health disaster is imminent. Microbiologist Steve Dealler and his boss, Professor Richard Lacey are veterans of food safety scandals and when BSE hits, it’s right up their street.

Steve is tasked with working out how many people have been exposed - and the news is not good. He’s convinced a major human health disaster is imminent - but the government keeps insisting beef is safe. The disconnect between his reality and everyone else’s nearly breaks him.

Written, presented and produced by Lucy Proctor.

It’s the mid 1980s and farm vet Colin Whitaker has the ominous realisation that a new disease is emerging in Kent’s cow herds. The Ministry of Agriculture, Fisheries and Food knows about it - and is determined to keep a lid on this potentially devastating news. But by 1987 officials know they have to act.

Government epidemiologist John Wilesmith is given a secret mission to find out how to stop the spread of what’s become known as BSE. He dons his wellies and works out one of the few things anyone can say for certain about the cause of the epidemic.

Written, presented and produced by Lucy Proctor.

Hidden deep in the heart of the Kent countryside is an abandoned factory with a dark past. In the 1980s and 1990s it processed tens of thousands of dead cows - some of which are thought to have been infected with a disease that would devastate British farming.

Then, when early human cases of BSE began to emerge in people living close to the rendering plant, paranoia also infected Kent’s countryside communities. People wanted answers - but there were none.

Today, science has failed to definitively answer two major questions about mad cow disease - where did it originally come from and how did humans get it?

Written, presented and produced by Lucy Proctor.