Prentiss Thompson is a man of many talents.
He has been a national karate champion, an investigator for the Essex County Prosecutor's Office and the author of an investigation into the Lafayette Bar and Grill murders.
The findings of that report have never been made public - until now.
The fluorescent light at the records department of the Passaic County Courthouse flickers on and off as we sit in the waiting area. Every so often the hatch cut into the office window opens, and a name is bellowed out.
After a wait of half an hour or so, we're called forward. The door next to the hatch swings open and out steps a woman, straining under the weight of the box in her arms.
"That's it - that's all we got," she says.
There are transcripts from both trials and from a secret grand jury in 1966. Buried at the bottom is something we - and hardly anyone else - even knew existed: the Prentiss Thompson report.
We look at each other, eyes wide. 'Do they know what they have given us?' we thought.
We decided to leave the courthouse swiftly, just in case the woman returned to take the report back.
We sat in the car for an hour reading the 45-page report. In 1975, Thompson was working alongside assemblyman Eldridge Hawkins, having been asked by the Governor of New Jersey to look into the case.
What Hawkins didn't know was Thompson, his investigative partner, was preparing his own report for the prosecutor's office. When Hawkins concluded his investigation, Thompson didn't.
Thompson won't talk to us. We have asked him twice. But getting hold of his detailed report has added more information and evidence to an alternative theory of the crime.
As well as this, we have all the other information gleaned from the Hurricane Tapes themselves, the private files of Detective De Simone and the various people we have spoken to throughout the series.
So there's only one thing left to do - head back to the United States to speak to John Artis and tell him what we've found.
- Episode one and two: 'This is the story of the Hurricane'
- Episode three: 'Cops don't like to have their backs to the door'
- Episode four: 'What are y'all? Bounty hunters?'
- Episode five: Meeting 'Chipmunk' and Carter's glass eye
- Episode six: Ali, Frazier & Dylan unite for Carter
- Episode seven: New Jersey v Carter & Artis - round two
- Episode eight: The Canadian commune & Carter's route to freedom
- Episode nine: Judge Sarokin, Carter - and a massive fish
- Episode ten: New characters, new theories, new conspiracies
- Listen: The Hurricane Tapes
Each week, BBC Sport will publish a new article to coincide with the latest episode of The Hurricane Tapes. A longer feature piece on the BBC World Service's investigation will then be published at the end of the podcast series. The tapes had been missing for nearly 10 years since author Ken Klonsky recorded a series of conversations with Carter for his book Eye Of The Hurricane: My Path From Darkness To Freedom. The audio contained in the tapes has not previously been heard by anyone other than Ken and Rubin Carter.