Sister Ardeth Platte, a Dominican order nun who fought for nuclear disarmament and later served as an inspiration for a character on the popular Netflix show Orange Is the New Black, died in her sleep at the Dorothy Day Catholic Worker House in Washington, D.C., on Sept. 30.

Platte, 84, who often worked in tandem with her best friend Sister Carol Gilbert, spent years in prison for nonviolent civil disobedience in opposition to nuclear weapons and war.

It was Gilbert who discovered Platte on the morning of Sept. 30. In recent years, the duo spent the brunt of their work speaking in support of the Treaty on the Prohibition of Nuclear Weapons. Gilbert said she had been excited that morning at the prospect of telling Platte that Malaysia had become the 46th nation to ratify the treaty.

Malaysia’s decision means just four additional ratifications are needed for the landmark disarmament treaty to be brought into force, Gilbert said.

Gilbert said Platte did her final Zoom presentation in support of the treaty on Saturday to the Boston University School of Theology.

Platte was born in Lansing, Mich., and began her work for the Dominicans as a teacher. In the 1960s and ’70s she served as director of alternative education at the former St. Joseph’s Educational Center in Saginaw, Mich.

It was in Michigan that Platte began her anti-nuclear work and where Gilbert joined her. Later, the pair moved to Baltimore to join the Jonah House resistance community with Elizabeth McAlister and Philip Berrigan.

In 2002, Platte, Gilbert and Sister Jackie Hudson gained international attention when they dressed as weapons inspectors, entered and were arrested at a Minuteman III nuclear missile site in Colorado. Convicted of federal felony charges, the three nuns were sentenced to prison.

When Platte and Gilbert returned to Colorado in 2017 for a rally, a story in The Denver Post stated: “In the years since they served their sentences in federal prison, the Dominican sisters, hardly deterred by the threat of future incarceration, have become pop culture icons.”

A character on Orange Is the New Black was based on Platte, who practiced yoga at Danbury Federal Correctional Institution with Piper Kerman, author of the book on which the series about a group of women serving time in a minimum- security women’s prison is based.

A documentary film about the sisters, called Conviction, led to stories about the trio being published in The New Yorker, The New York Times and The Washington Post, as well as some international publications.

In an email announcement of Platte’s sudden death sent to many of her friends, Catholic activist Paul Magno of Jonah House wrote: “Deep shock to hear this but grateful for all that Ardeth has given to making the peace of Christ radiate through our world.”

In 2017, Platte told The Denver Post: “I refuse to have an enemy. I simply won’t.”