Poor, little rich girl or heartless killer? That’s the question posed by Showtrial, the latest drama from the company behind Line of Duty and Vigil, World Productions. But BBC One’s current Sunday-night series is far more than a whodunit.

Posh, arrogant and, frankly, thoroughly unlikeable, Talitha Campbell (played by Celine Buckens) has been charged with conspiring to murder a fellow university student. She chooses Cleo Roberts (Tracy Ifeachor), the duty solicitor on the night of her arrest, to lead her defence against a prosecution set on using her privilege and sexual behaviour against her.

The 5x60-minute drama, which began its run at the end of last month, escalates from a routine murder investigation to a national talking point, becoming, in effect, a show trial.

The series “uses the DNA of our true-crime obsession to create a gripping fictional murder trial that shines a light on the failings of our justice system”, according to World Productions’ CEO Simon Heath.

Creator and writer Ben Richards set out to explore how the right to a fair trial and the idea of reasonable doubt can be distorted when a woman’s “past and sexuality have been brought into play”.

“Many cases have fed into the making of Showtrial; it borrows from a lot of different places. Issues of class, race and gender are really important in the show, but they’re being revealed by the show; they’re not necessarily driving it,” explained Richards, who was talking at an RTS event in October.

The writer, whose impressive tele­vision CV includes Spooks, The Tunnel and current Sky One hit drama Cobra, added: “It may well be the case that, on balance, you might think Talitha is guilty but that’s not enough – you have to prove this case so that people don’t have reasonable doubt about it.… [Showtrial] asks a lot of moral questions about the justice system.”

Buckens, who starred in the Netflix series Free Rein, was thrilled to get the nod for the role and to play such a “layered and complex character”. She said: “She’s a character who is clearly very, very privileged but her experience growing up… wasn’t solely positive. There’s a dark side that’s explored [in the drama]. The other aspect of Talitha is her sexuality, which people really seize on and make a cornerstone of her identity in a way that is unfair and, I think, gendered.”

Since appearing in Doctor Who 12 years ago, Ifeachor has built a successful career in the US, recently starring in action series Treadstone. “It’s great to come back to England and do something that really matters, and not just [as a] story, but that matters to my community and everybody who looks like me,” said the British Nigerian actor. “I’ve always had such a love of the legal system and I actually wanted to be a lawyer – it was [a choice] between law and acting.”

To prepare for the role, Ifeachor attended a couple of court cases in Bristol, where Showtrial is set and was filmed. She also sat in with two barristers during pre-trial discussions. “It was amazing the way they talked to each other and the way they used the legal system to the advantage of their client, even if they knew their client was guilty,” she said.

Ifeachor also sought advice from real-life black solicitor advocate Cecilia Goodwin: “I wanted to find someone who looked like Cleo, was about her age and doing what Cleo does.”

Director Zara Hayes is a leading documentary film-maker who has recently turned to drama. Her debut movie, Poms, starring acting legend Diana Keaton, was released in 2019.

On the surface, Showtrial’s two leads are playing wildly contrasting characters but, said Hayes: “These two women see something in each other from the beginning… they have very different life experiences but they’re not pleasers. So much of the female role from a young age is about pleasing people.

“Something that really drew me to the script and these lead characters, in particular, is to see women who aren’t just immediately trying to put other people at ease, making them laugh or flirting with them or whatever those things are that women are meant to do in [such] situations. There’s a kind of anarchy to both of them, a rebel status, that I love.”

Buckens added: “The fact that Talitha doesn’t please and that she’s unlikeable… doesn’t mean she’s guilty – that was the crux of [Showtrial] for me.… The show forces you to go beyond your snap judgements.”

Ifeachor concurred: “As a woman, we don’t get to walk into [a room] in the same way as a middle-class man.… Both Cleo and Talitha understand what it’s like to be on the receiving end of a snap judgement.”

Like Ifeachor, Hayes once thought about a career in law and remains fascinated by it: “[We have] the best imperfect system that we could find, yet it’s really flawed.”

Showtrial drew on legal and police advisers throughout the production process. “We had a barrister on set with us,” recalled Hayes. He was able to step in when the script took too many liberties with English law. “We’re all so used to watching American stuff that some of the ideas we had about how we should [shoot] certain scenes were coming from this fictional American system…”

Richards interrupted, joking: “I’d have had them shouting ‘objection’ and a judge with a gavel…”

Hayes continued: “There’s always a line between good drama and storytelling and being true to [the law], but we tried to [tread] the line carefully and be as authentic as we could be.”

Richards added a riposte: “I don’t care, let them go on Twitter and moan about it.”

Showtrial raises some searching questions about the the English legal system but, said Richards: “Over and above all else, we want people to be gripped and be talking about, ‘Did she do it?’ – that’s the essence of the show.”

Report by Matthew Bell. The RTS event ‘Showtrial preview and Q&A’ was held on 27 October, chaired by Yasmin Evans and produced by the RTS and the BBC.