There are many questions swirling around the death of Sister Catherine “Cathy” Cesnik, a beloved 26-year-old nun and teacher in Baltimore found fatally beaten on a freezing January day in 1970, two months after vanishing from her apartment.
Cesnik’s homicide remains unsolved, even as police tell PEOPLE the case is active, with one living (but unidentified) suspect.
The Keepers, a new true crime documentary series premiering on Netflix on Friday, spotlights Cesnik’s killing and the mysteries she left behind: Who would want a nun dead? And what did Cesnik know before she died?
For years, her younger sister Marilyn Cesnik Radakovic believed she was the victim of a random act of violence. But her opinion changed in 2016 when Radakovic learned that the Catholic high school where Cesnik had recently taught English, Archbishop Keough, may have been concealing a history of sexual abuse — and Cesnik may have known about it before her death.
Jean Wehner, one of Cesnik’s former students, tells PEOPLE, “I think Cathy was planning to go to the police about what was happening to us girls at Keough.”
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Wehner, who is featured in The Keepers, was one of two women in the early ’90s who publicly accused Father A. Joseph Maskell of sexually abusing them while he worked as Keough’s chaplain and school counselor from 1967 to 1975.
Others later came forward, describing how they were sexually and psychologically abused by Maskell.
Maskell denied the accusations and was never charged. But the church removed him from his position as a priest in 1994, and church officials have said they believe he was sexually abusive. He died in 2001.
Some survivors recount in The Keepers how nothing was done to stop Maskell’s abuse — but a spokesman for the Archdiocese of Baltimore, Sean Caine, disputes this characterization, saying the church first learned of the allegations in 1992.
Baltimore County police are investigating multiple angles on Cesnik’s homicide, including possible connections to Maskell’s abuse and if there are links between her death and three other unsolved killings in the area.
“We have never proven that Sister Cathy was killed because of her knowledge of abuse in the Roman Catholic church,” police spokeswoman Elise Armacost says.
Police said Maskell’s body was exhumed in February for DNA testing in Cesnik’s case and it was not a match.
Radakovic, who also participated in The Keepers, tells PEOPLE she wants answers to what happened to her sister nearly five decades ago.
The example of Wehner and other survivors should be inspiring, she says:
“I think people should take Jeanie’s courage, that she had the courage to do this, and they should have the same courage to solve this crime and to solve it correctly.”