The series gives unprecedented access, granted by Glasgow High Court, to a high-profile murder trial that has gripped Scotland and solves a 20-year old disappearance.

The exclusive access documented suspects Edward Cairney and Avril Jones as they faced trial for the murder of Margaret Fleming.

When a Personal Independence Payment application – a welfare benefit for someone with a disability – was submitted in 2016, suspicions were raised when authorities couldn’t contact the claimant.

The claim was made under the name Margaret Fleming, a 35-year-old woman who had seemingly vanished from a remote costal village in Scotland.

Fleming was a vulnerable adult and was supposed to be under the full-time care of Cairney and Jones. However, when police asked neighbours about Fleming, they said they hadn’t seen her for nearly 20 years.

Just before Christmas in 1999, Fleming – who was 19 at the time – vanished and yet no one reported her missing.

Cairney and Jones stand accused of murdering her, disposing of her body and claiming benefits in her name for 16 years.

The trial delves into the inner workings of Scotland’s justice system and social care system, as the investigation attempts to uncover the truth about what happened to Margaret Fleming.

Controller of BBC Two, Patrick Holland commented: “This is a ground-breaking documentary for BBC Two that takes the audience into the very centre of a trial that gripped a nation.”

“We have been delighted with the audience response to our Murder Case series, which was made by the same team,” added David Harron, Commissioning Executive at BBC Scotland.

“And this promises to give audiences yet another fascinating look at the work which goes on behind the scenes of Scotland’s justice system.”

The series was produced by Firecrest Films and will premiere on BBC Scotland followed by BBC Two.