You can't blame Netflix for trying to recreate the success of Making a Murderer. The true crime series became the service's most talked about documentary when it was released at the end of 2015. 

It's the investigation that challenged all comfortable notions of American justice and the rule of law. It reached as far as the White House, and almost contributed to a man's release from prison.

That is the legacy which Netflix's new true crime series, The Keepers, has to contend with.

In many ways the comparison is unfair. Director Ryan White has been working on The Keepers for three years, beginning well before Making a Murderer was released. The case – involving the murder of Sister Cathy Cesnik and the alleged cover-up of horrific child abuse at a Catholic high school in Baltimore – is very different. The issues explored, the people involved, the stories brought to light – all deserve to be heard on their own terms.

Yet still, The Keepers will inevitably have to face the question: is it the new Making a Murderer?

"I’m not frustrated by the comparison," White says. "Nobody has seen The Keepers yet. I think Making a Murderer and The Jinx and Serial, all of these true crime phenomenon have paved the way for The Keepers."

"I hope when people see it they will realise that it’s very different," he adds.

And he's right. Where Making a Murderer focuses on the dispensing of dubious justice, The Keepers is about the absence of any meaningful justice.

What's the story behind Netflix's true crime series The Keepers?

After almost 50 years, Sister Cathy's murder remains unsolved. The Keepers follows a small but dedicated group of amateur detectives – former pupils of Cathy, journalists, retired police officers – who are still trying to find out what happened, still trying to explain why someone would want to kill a well-loved high school teacher and nun. 

"If we’re talking about [comparisons with] Making a Murderer, then a lot of our focus in The Keepers is on the victim, Sister Cathy," White explains.

"Cathy is probably the main character in the film, although she died in 1970. As you’ll see in the series, her family plays a large part in 'bringing her to life'. Everybody around her – her students, her colleagues, her friends – are also bringing her to life.

"It’s not necessarily about the perpetrator, like a lot of true crime series are. Of course we’re asking the question, ‘Who killed her?’ but it’s also about her life."

As viewers of The Keepers will discover however, this story isn't just about Cathy's life and death. The focus widens to include first-hand accounts from former pupils of Archbishop Keough High School, the school where Sister Cathy worked. Their testimony tells of sexual assault by priests involved with the school, and the possibility that Cathy was killed in order to cover up those crimes.

"It’s also about child sex abuse, and that’s a dark, heavy subject matter," White says. "It’s not a subject matter people like to talk about. For whatever reason, people like to discuss and investigate murder, but they don’t really want to talk about child sex abuse.

"And that, unfortunately, is the dark underbelly of this entire story. What we’re looking at is, yes, a murder, but it’s also about the foundational crimes that may have led to that murder."

If there is a connection with Making a Murderer, Serial and The Keepers, it's that they're all concerned with 'telling a story right', with all the responsibility that entails. They all offer a voice to people who have been wronged, but also attempt to 'right' that wrong through the very telling – to deliver a public reckoning for crime that would otherwise have remained private, hushed up, buried.

"Series like that were able to percolate the mainstream conversation and not just get relegated to the documentary world," White says.

"Those series have allowed us to reach a wider audience, and that’s the point of The Keepers. The point is to bring the truth to light, and if you can’t bring the truth to light to a lot of people, then that truth will always stay only in a certain sector. I’m grateful for those series, but I hope when people see it they will realise that it’s very different."

All seven episodes of The Keepers will be released on Netflix on Friday 19th May