Man Whose Wife Murdered Mistress Before Suicide Says She Would Have Killed Him If He Walked in First

Mark Gerardot told Dr. Oz that his estranged wife, Jennair, had a "plan B" to kill him if he'd interrupted her planned murder of Meredith Chapman

After discovering the bodies of his mistress and estranged wife, both shot dead in a murder-suicide, Mark Gerardot learned that he was a potential target, too.

A 15-page letter left behind by the killer — his wife of 24 years, Jennair — revealed what Mark described to Dr. Mehmet Oz as “her plan B,” which was to kill Mark if he was the first to enter the home of Meredith Chapman, the woman Jennair murdered before killing herself.

“I was going to be the backup plan, to take me out,” Mark said Thursday on a broadcast episode of The Dr. Oz Show.

Meredith, a Villanova University assistant vice president, and Jennair died on April 23, 2018, inside Meredith’s upscale residence on Philadelphia’s affluent Main Line, where Jannair broke in and lay in wait after canceling a dinner plan with Mark.

Mark and Jennair had been scheduled to meet to discuss their pending divorce when Jennair cancelled by text — and then sent him increasingly alarming messages. “You ruined my life,” said one. “I hope you never find happiness,” said another, followed by, “Bye, Mark,” Mark said in an interview last month on ABC’s 20/20.

Mark and Jennair Gerardot

• Want to keep up with the latest crime coverage? Click here to get breaking crime news, ongoing trial coverage and details of intriguing unsolved cases in the True Crime Newsletter.

Mark then drove to Meredith’s house fearing there would be a confrontation between the two women — and encountered both of their bodies.

“There was a letter that she wrote,” Mark told Dr. Oz. “And she described in great detail what she was going to do. She was afraid of me walking in first. She says, ‘If he does, I’m going to have to do a Brynn Phil Hartman.’ Phil Hartman was a famous actor on Saturday Night Live and he and his wife took it,” with Brynn shooting her husband before she took her own life. “She used their names as verbs, as to what she was going to do. I was going to be the backup plan, to take me out.”

Meredith Chapman
Meredith Chapman.

The affair between Mark and Meredith had started with shared emotional intimacies over drinks in late 2017, soon after Meredith hired Mark for a job in the marketing department at the University of Delaware, where Meredith then worked.

Accepting the job required Mark to briefly leave Jennair behind in South Carolina, where they were living at the time. But already the couple’s marriage was struggling, he told 20/20. Meredith, too, confessed to him that she was also in an unhappy marriage, and before Jennair moved north, Mark and Meredith had expressed their love for one another, he says.

Jennair sensed the change in her husband. “She finally asked me, ‘What is up with you? You’re acting different,’” says Mark. “She said specifically, ‘It’s Meredith, isn’t it?'”

Mark announced his intent to leave Jennair but still entered counseling with her. He also continued to see Meredith, who switched jobs from the University of Delaware to Villanova and moved to the Philadelphia area while separating from her own husband of nine years.

Mark Gerardot and Dr. Oz
Mark Gerardot, at left, and Dr. Mehmet Oz. Sony Pictures Television

Meanwhile, Mark’s acknowledged affair became an obsession for Jennair. She placed tracking devices on the cars driven by Mark and Meredith, and sewed listening devices into Mark’s clothes to secretly record his conversations.

One of those recordings captured Jennair’s rising insecurities.

“You don’t find me appealing,” Jennair told her husband, according to the audio obtained by 20/20. “You don’t find me attractive. You don’t want me anymore. You don’t even like me. You are miserable.”

Police who later recovered a series of text messages and emails written by Jennair said they pointed to revenge as her motive for Meredith’s murder.

Related Articles