The search for a killer clown
Marlene Warren answered the door to her Wellington, Fla., home and was fatally gunned down by a mysterious clown. Despite eyewitnesses and a mountain of circumstantial evidence, investigators were unable to make an arrest in the case for nearly 30 years.
WATCH: "48 Hours:" The Clown Did It
This is a clown painting that Marlene Warren completed when she was about 14 years old. When she was 40, she was fatally gunned down by a shooter dressed as a clown
Marlene and Mike
Marlene Ahrens was 20 years old, and had just ended her first marriage, when she married Mike Warren.
The Family
Mike became a second father to Marlene's sons, Johnny and Joe.
"When we were younger, he was great," Joe Ahrens recalled to "48 Hours," "the only dad I knew."
The Aero Club
In the late 1980s, the Warrens moved into a home in the Aero Club in Wellington, Fla. -- a community where every house has access to a private runway.
Bargain Motors
Mike and Marlene owned several businesses together including Bargain Motors, a used car and rental business that was in Marlene's name. They couple also owned a group of rental properties in West Palm Beach, an airplane, and racehorses
The First Tragedy
In the fall of 1988, John Ahrens Jr. was tragically killed in a car accident; he was only 22 years old. That's when Joe remembers Mike and Marlene's marriage starting to falter.
"He wasn't around as much as … you'd say he should have been," Joe told "48 Hours."
May 26, 1990
In May 1990, a year-and-a-half after Johnny's death, in May 1990, Marlene answered her front door and was gunned down by a clown bearing balloons and flowers. Her son Joe and three of his friends witnessed the attack.
Murder Case
After she was shot in the face, Marlene Warren was rushed to a nearby hospital. The 40-year-old would remain in critical condition for three days, before she was removed from life-support and died.
The Investigation
The Palm Beach County Sheriff's Dept. detectives were immediately on the case and were on the lookout for an armed and dangerous clown. Three hours after the shooting, they received an anonymous tip to look into Marlene's husband, Mike.
Mike Warren's Alibi
When police reached Marlene's husband Mike, he said that at the time of the shooting he was miles away, driving to the horse track with friends -- what appeared to be an airtight alibi.
Sheila Keen
The anonymous caller had also given police a second name -- Sheila Keen. Keen was a 26-year-old mother, estranged from her husband and worked for Mike Warren repossessing cars. There were rumors she was having an affair with Mike
The Balloons & Flowers
The balloons and flowers were recovered from the scene, and investigators immediately tried to track down where they could have been purchased. Within days, they were able to link them back to a specific supermarket.
The Balloons & Flowers
The balloons and flowers were recovered from the scene, and investigators immediately tried to track down where they could have been purchased. Within days, they were able to link them back to a specific supermarket.
Publix
Investigators were able to link the flowers and balloons to this Publix Supermarket, and learned that the woman who purchased them matched Sheila Keen's description.
Costume Shop Employees
Two employees at Capezio Spotlight costume shop remembered a clown costume being purchased two days before the murder. Detectives learned the customer was a woman with long brown hair and got a "tentative identification" for Sheila Keen.
The LeBaron
Four days after Marlene Warren was shot, police found this white Chrysler LeBaron in a parking lot eight miles from the crime scene. Marlene's son Joe remembered seeing the clown drive away in a car fitting this description. Inside police found orange fibers that resembled hair from a clown wig and several strands of brown human hair.
Sheila Keen's Apartment
The same day police found the LeBaron, they obtained a warrant to search Sheila Keen's apartment. Police reports say they found orange fibers on clothing inside her home -- resembling fibers from a clown wig.
Cold Case
Despite circumstantial evidence that pointed to Sheila Keen as a suspect in the case, police made no arrests in the months and years following Marlene's murder. In 2013, they reopened the case, and ran DNA again, that would soon heat up when the results came back with a match that made police feel certain they'd finally found their clown.
New Life, New Name
While they continued their investigation in Florida, police would learn that Mike and Sheila had gotten married in 2002 and were living in Tennessee. They were running this burger joint called the "Purple Cow," and their employees and neighbors told 48 Hours that while Sheila changed her last name to Warren, she was also using a new first name: "Debbie."
An Arrest
On Sept. 26, 2017 -- 27 years after Marlene's murder -- Sheila Keen Warren was arrested for first degree murder. Sheila is in a Palm Beach County jail awaiting trial, and, if convicted, could face the death penalty.