A Florida Mom Opened Her Door to a Clown Who Shot Her at Point Blank Range. Who Killed Marlene Warren?

It was Memorial Day weekend in 1990 and Joe Ahrens was looking forward to hanging out with his friends.

Ahrens, 21, was eating breakfast and watching TV with some of his friends who stayed overnight at his house in Wellington, Fla., in Palm Beach County when someone knocked at the door.

His mother, Marlene Warren, 40, went to see who it was. When she opened the door, she saw what appeared to be a delivery person wearing a clown costume, a wig and clown makeup, holding a basket of flowers and carrying balloons.

“How pretty!” Ahrens heard his mother say. Seconds later, the clown pulled out a gun and shot Warren in the mouth at point blank range.

Frantic, Ahrens rushed to his mother’s side, just as the clown was turning to leave.

In that moment, “the clown looked me right in the eyes and I got to glimpse those eyes,” he recalls in this exclusive clip (shown below) the next episode of People Magazine Investigates on Investigation Discovery/ID and streaming on Max. “They were big and brown.”

Airing on Monday, Nov. 4 at 9/8 c, the episode, “Sex. Clowns. Murder,” goes in-depth on the bizarre killing that went unsolved for 27 years.

The episode details how dogged Palm Beach County investigators searched for Warren’s killer, finally arresting a suspect in 2017 who had a surprising connection to the victim. 

“Our goal in this office is to do justice,” Palm Beach County State Attorney Dave Aronberg told PEOPLE that year. “We are going to do justice for Marlene Warren.”

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Investigators questioned her husband Michael, who was Warren’s second husband, having married him in 1972. They zeroed in on the couple’s troubled relationship.

Just a week before her death, Warren had told Ahrens that Michael Warren, Ahrens’ stepfather, had ceased to “care anymore” after the sudden death of her 22-year-old son John in 1988. Unhappy in the marriage, she wanted to leave, Ahrens said.

For more about Marlene Warren’s bizarre death, subscribe now to PEOPLE or pick up this week’s issue, on newsstands Friday.

But Michael Warren had an alibi: He was driving to Miami when his wife was shot. He was never arrested or charged in connection with his wife’s murder.

So police turned their attention to other people who may have wanted the well-liked mother of two dead.

For more on Marlene Warren’s death, tune in to the next episode of People Magazine Investigates — “Sex. Clowns. Murder.” — airing on Monday, Nov. 4, at 9/8 c, on Investigation Discovery/ID and streaming on Max.