Telling the tale of a serial killer who manipulated and gaslit his victims, true crime series The Sixth Commandment has been hailed as one of the dramas of the year. Writer Sarah Phelps and producers Brian Woods and Derek Wax reveal how this story came to the screen.
“In the late 1990s and early 2000s, every [fictional] serial killer had read Dante and understood Hell, or at least they’d read the SparkNotes – Se7en and Silence of the Lambs created many monsters,” says Sarah Phelps, the writer who is best known for her Agatha Christie adaptations and is now behind the BBC’s genre-bending true crime drama The Sixth Commandment.
“I enjoy [those types of films], but there’s a danger in writers focusing on giving the killer a backstory and interiority at the expense of the victim. You’re writing about the human heart, people who want love, feel joy, have dreams and are beautiful and precious.”
Phelps took this to heart when writing The Sixth Commandment. The drama is based on the strange story of a much-loved teacher, Peter Farquhar – played by Timothy Spall in a career-best performance – who spent his life battling the conflict between his sexuality and his Christian faith until he was murdered by a former student, Ben Field, who pretended to love him as a ruse to inherit his estate.
Initially succeeding in making Farquhar’s death look accidental, Field (Éanna Hardwicke) promptly moved in next door and began the same process with elderly neighbour Ann Moore-Martin (Anne Reid), securing a place in her will too. He would eventually be convicted of Farquhar’s murder, but the police couldn’t prove he was ultimately responsible for Moore-Martin’s subsequent death.
Phelps tells the story in four episodes. The first is a gentle portrait of Farquhar and his loneliness, while the second is an account of Ann falling for this young man. The police arrive in the third episode, and the fourth is a near-verbatim recreation of the court case that followed, with some extensive flashbacks to keep the victims present.
“Peter was romantic,” she explains. “He loved the romance poems, so I tried to tell the story in a poetic style. He is lost in a deep, dark, thorny forest and yearns for someone to slash through the trees and wake him with a kiss. With Anne, the police were investigating her suspect illness when she died. With true crime, you get to know the victim retroactively. The killer is usually one step ahead. I did not want to give the killer power. I wanted to write about people being glamourised in the traditional sense but not to let him glamourise me or the audience. He is cruel.”
The show’s route to the screen was unconventional, beginning with a true crime documentary series called Catching a Killer that follows Thames Valley Police’s Major Crime Unit on murder investigations. “It usually follows the same pattern,” says producer Brian Woods, who runs factual entertainment company True Vision, which makes the programme.
“They’ll call and say there’s a briefing in two hours. We rush up to Oxford and film it. It generally then takes 48 to 72 hours to catching the killer or proving the case, and then there’s the slow burn to trial. On this one [the case featured in The Sixth Commandment], the inspector said, ‘It’ll be a slow burn.’ It took two years to get to court.”
Woods was chatting about the case with Derek Wax, a friend who produced Sex Traffic for Channel 4 and The Rig for Amazon through Wild Mercury Productions. “I’d been a pupil at a school Peter taught at,” he says. “I saw him playing Miss Prism in the teachers’ version of The Importance of Being Earnest. I started talking to Brian about how this could become a drama – the documentary he made was excellent, but there was so little footage of Peter and Ann.”
Farquhar had kept detailed daily diaries, and when the filmmakers read them, they found the “well of loneliness and repression that gay men of that generation in the church had suffered,” Wax says.
The BBC commissioned four episodes and approached Phelps immediately. “She was able to grasp the tone needed to tell the story in the most compelling and compassionate way,” Wax says. “She doesn’t rely on writers’ rooms. She gives scenes power and subtext while preserving the mundanity of ordinary conversation.”
The Salisbury Poisonings director Saul Dibb came on board next, and he immersed himself in the 1944 film Gaslight, the source of the term for convincing someone their memories aren’t real and that they may be going mad.
“Field appears incredibly charming, luring Peter and Ann in, and then they are made to believe things that aren’t true,” Dibb says. “In Gaslight, they don’t mess about – the first shot is of a flickering candle on the wall of a house, so you understand immediately that something’s up. So it was important for me that the first thing you see is Peter putting the kettle on. Throughout the series, there’s a continual sense of this very English thing. What better way to carry poison into the hearts of Middle England than through cups of tea?”
Dibb was responsible for casting Spall – his only choice for the part of Peter. “When Tim and I discussed the role, I realised that these two people [Spall and Farquhar] shared a lot in common, a fascination with the world and ideas,” he says. “Tim knows a lot about art, literature and poetry, all those things that fascinated Peter throughout his life. It also felt important that the three older people – Peter, Ann and Liz – should be played by actors who have a certain recognisability and credibility that then allows us to introduce Field as a relatively unknown character, somebody who carries no baggage whatsoever.”
Meanwhile, Hardwicke had Normal People on his CV, and a natural charm, but his audition showed he could play far darker, says Wax.
Hardwicke himself says he found the role shocking. “Playing Ben felt a bit like going into a labyrinth,” he says carefully. “I had to set aside any horror and disgust I might have felt. his chief motivation seems to be a pathological need to manipulate, hurt and have power over others.”
Although the show is steeped in the life of an English village and the quirks of gay British history, Wax is hoping it will reach an audience around the world via distributor Banijay Rights. “It is not just a niche story – it has wider themes and interests. One is loneliness – older people living like The Beatles song Eleanor Rigby, widowed or widowers or not having found love, living alone and how little we know about inner emotional lives. It’s not the whodunit that grabs you, it’s how much you care for these people.”