On Sunday June 30 1974, Alberta Christine Williams King played “The Lord’s Prayer” on the organ of Ebenezer Baptist, the church where her father, A.D. Williams, her husband, Martin Luther King Sr., and son, Martin Luther King Jr., all had served as pastors.

The song finished, and most of the congregation had their eyes closed and heads bowed in preparation for prayer when they heard a shout: “I’m taking over here!”

They looked up to see a young black man standing on a pew near the front of the church. He jumped down, bolted to the pulpit, faced the choir, and pulled out a gun.

“It seemed like I was watching a scene from a bad movie play out,” Christine King Farris, Alberta’s daughter, would recall in her 2009 memoir Through It All.

The man—Marcus Wayne Chenault Jr.—fired every round in his gun, hitting Alberta King, church deacon, Edward Boykin, and congregation member Jimmie Mitchell. As the gunman sprinted out the side door leading to Jackson Street, the sanctuary was chaotic.

Farris eventually made her way outside. As she later described the scene:

There were people everywhere. There was a throng of onlookers. When I looked in their eyes I saw what is often described as “the thousand-yard stare.” It was a kind of blankness I’d never seen before. There were bewildered and in shock. Many were crying; most had their hands pressed to their mouths in disbelief.

Farris and other family members made it to Grady hospital, where they learned that dean Boykin and Mrs. King had died.

That Sunday was “without question the worst day of my life,” wrote Farris. Her brother Martin had been assassinated in Memphis six years earlier, her brother A.D. drowned a year after that. “I thought I had made it through the worst days of my life. I was wrong.”

Although Chenault’s lawyers pleaded insanity—the young man repeatedly said he was on a mission to kill all Christians—he was given a death sentence. This was later reduced to life in prison, in part at the insistence of King family members who opposed the death penalty. He died in prison of a stroke in 1995.

Photograph: Alberta and Martin Luther King Sr., Courtesy of Jim Peppler Collection, Alabama Department of Archives and History