“I don’t care what you think. I don’t care what your opinion is. I don’t give a monkey’s. You’re the advocate.” Master John Leslie, who deals daily in the High Court with advocates making procedural submissions, was putting an aspiring barrister through her paces. “I hope I’m not too brutal,” he said in an aside to camera, in a new television series, The Barristers. “But in order to bring something home, you need to be direct — you can’t pussy-foot around and say ‘well done’ when mistakes have been made that can be corrected and ought to be corrected.”

This is the world of barristers and the Bar. For the first time in its 800-year history, it will be exposed to the public in a ground-breaking documentary series starting on Friday, November 14.

The four-part series, co-funded by the BBC and the Open University, goes behind the scenes of the justice system, into the courts, robing rooms and Inns of Court, and records a profession facing change against a backdrop of ancient traditions.

Produced by Lynn Barlow, whose team also made the award-winning Anatomy of a Crime for BBC Two, the series is unprecedented. Cameras are banned by statute from the courts in England and Wales but the production team followed barristers into court (from the Old Bailey to a law lords’ hearing), slipping out before the judges entered. It also broke ground in the access gained to a profession that can be defensive and suspicious in the face of media coverage.

Barlow, from the BBC’s documentaries unit in Bristol, said that it took two years to win the necessary approvals and another two to film. In all, 400 hours of film were cut to four. “Some barristers were enormously suspicious and hostile at first — they thought we’d stitch them up. All we wanted to do was hold a mirror up — we didn’t have an agenda.” The Bar, she added, was full of dedicated and fascinating people and “at this particular time is very much under public scrutiny and facing huge changes”.

A succession of Bar chairmen were positive and patience paid off. Small teams were sent to Birmingham and London. The series follows students including Catherine Piercy, Kakoly Pande, Iqbal Mohammed and Anna Dowuona-Kludze as they take their first steps into the profession after the Bar Vocational Course, through interviews, the scramble for pupillage and a tenancy. Only one in five out of thousands will ever get to stand on their feet in court.

A preview of clips seems to show a warts-and-all picture of the Bar, complete with some of its characters. Dickie Bond, prosecuting counsel, lands the defence with damning CCTV evidence just before trial. He tells the camera: “We anticipate that this afternoon he [the defendant] will plead guilty to the offence — because he’s stuffed.”

Two barristers on opposing sides — prosecuting and defence — have a coffee at a local café. It’s like professional footballers, one explained: “I’m sure Rooney and Gerrard see each other at the pub and might have a drink but when it comes to the match they are like demons for their own team.”

The cameras follow a woman barrister into a history-steeped courtroom of the Old Bailey before trial. She is a Crown prosecutor — a “standard bearer” for the Crown Prosecution Service — taking a murder case. “I’ve got some of the most experienced barristers against me — the leader of the circuit, the chairman of the Criminal Bar are two of the QCs against me. Lots of very experienced people . . . but I mustn’t let that put me off.”

Professor Gary Slapper, director of the OU law programme and legal consultant to the series, said that the aim was to “give a clear, fair and balanced exposure to the erstwhile cloistered Bar”, adding: “It’s an immensely important part of the machinery of democracy and civilisation but its daily workings and professional life haven’t really been covered in any sustained documentary film series.” The skill, he said, was to ensure that the film did this yet remained cutting-edge and entertaining.

The Bar had no final say but there was a carefully worded agreement to ensure that both sides were happy. “The Bar and the BBC are both self-confident institutions . . . the process was a bit like two people who can only climb out of a well by leaning back to back.”

The series cost £1 million. Barlow is content with what looks like a quality result. “The perception is that the Bar is full of very rich people. But it’s not that . . . although you do have to be very, very clever and academically able. It is meritocratic.”

The Barristers begins on BBC Two on Friday, November 14 at 9pm. The four episodes will screen weekly

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