An angry and bitter cousin of Barry Sherman has failed a lie detector test after making unsubstantiated allegations that the former Apotex CEO was part of an aborted plot to kill his wife two decades ago.

In an interview to be broadcast Friday on CBC's The Fifth Estate, Kerry Winter claims that Sherman asked him to arrange the killing of the pharmaceutical executive's wife on two occasions in the late 1990s.

Billionaire Barry Sherman and his philanthropist wife, Honey Sherman, were found dead in the pool area of their Toronto mansion on Dec. 15. Toronto police say the couple were the victims of a targeted double homicide.

Winter told The Fifth Estate he was going public now with the allegations because he wanted to "hurt" Barry Sherman's legacy.

I was betrayed. My cousin hurt me, and now I want to hurt him. - Kerry Winter

Winter and his siblings had been locked in a protracted, decade-long lawsuit launched in 2007 seeking a piece of the Apotex fortune. Last September, an Ontario Superior Court judge dismissed the case as "fanciful." The cousins have since appealed.

"I was betrayed. My cousin hurt me, and now I want to hurt him," Winter told The Fifth Estate.

As part of the court's decision, Winter not only lost his claim on his cousin's fortune, but he was also ordered to pay Sherman back $8 million. Just a week before the Shermans were found dead, a court ordered Winter and his siblings to pay Sherman $300,000 in legal costs.

Winter's bizarre allegation of the plot to kill Honey Sherman includes the claim that he lined up a hit man to do the job two decades ago.

"He said, 'I want you to whack my wife,'" Winter claimed. Winter then claimed the plan was aborted at the last minute.

"I called him and said: 'You know, there's no turning back, Barry, if I push the button,'" Winter said.

The Fifth Estate interviewed two of Winter's friends who said they were told of the plot two decades ago, but neither had any direct knowledge of such a plot ever happening.

Some of Winter's claims were reported this week by Canadian and U.K. media outlets, but The Fifth Estate could find no direct evidence to support Winter's claim that he and Barry Sherman were involved in a conspiracy to commit murder.

Winter and his lawyer agreed to a lie detector test on the question of whether or not Barry Sherman had asked him to arrange the killing of his wife.

Apotex founder Barry Sherman and his wife, Honey, are seen in this undated photograph. (United Jewish Appeal/Canadian Press)

The test, filmed by The Fifth Estate, was conducted by former Quebec police officer and veteran polygraph expert John Galianos.

Galianos determined that Winter was not being truthful about the alleged plot and that he "failed" the test.

While not admissible in court because of possible inaccuracies, polygraphs are commonly used by police officers to determine truthfulness.

Winter told Galianos on camera that he "embellished" part of the scheme. He also said he fabricated other parts of the story.

"He was lying, and the test results — the polygraphist — confirms that," said Michael Arntfield, a criminologist at Western University in London, Ont., who observed the polygraph test.

"I mean, why go through this whole song and dance? That's really the underlying question here."

Late Thursday, Winter sent The Fifth Estate results of another polygraph test he says he arranged himself that showed the results were "inconclusive."

On the advice of his lawyer, Winter also declined to take a lie detector test on the question of whether he killed the Shermans.

Winter admits he could be seen as a suspect in the Sherman killings.

"I probably had reasons to lash out to do the dirty deed," he told The Fifth Estate's Bob McKeown. "I had nothing to do with it. I don't know who did it."

'I would talk about killing Barry'

In a wide-ranging interview with The Fifth Estate, Winter said he told his psychiatrist that in the past, he had fantasized about murdering Barry Sherman.

"I would talk about killing Barry, and it was very graphic," Winter said. "He would come out of the parking lot of Apotex, and I'd be hiding behind a car, and I'd just decapitate him. I wanted to roll his head down the parking lot, and I'd sit there and wait for the police."

Toronto police were investigating at the Sherman home for several weeks after the bodies were found on Dec. 15, 2017. (Evan Mitsui/CBC)

Winter says no one can verify where he was at all times on Dec. 13, the day Barry and Honey Sherman were last seen alive.

"No, no alibi," he told The Fifth Estate. He said after a Cocaine Anonymous meeting, he went home and fell asleep.

"Very easy for me to have left work at any time because I'm not on the clock. ... I could easily have driven over to [the Sherman home] and did the deed.

"I admit to that, but I didn't, I didn't, and that's why I'm not nervous."

Winter said he planned to meet police for an interview and that he was told he was not a suspect.

Winter claims that Barry Sherman asked him to arrange the killing of the pharmaceutical executive’s wife on two occasions in the late 1990s. (CBC)

Arntfield, who is also a former major crimes police officer, says Winter's story will be of interest to the police.

"He needs to be properly cleared before moving on to other people, I would say."

After his interviews with The Fifth Estate, Winter reached out again to say that even though he did not retract anything, he did not want to "come across as uncaring, unfeeling."

"This was a tragedy no matter how you slice and dice it," he said. "This was a terrible thing that happened, even though my cousin and I had an extreme falling out."

The Fifth Estate has no evidence of Winter's involvement with the Sherman homicides.

Please send tips on the Sherman story to fifthtips@cbc.ca or call Harvey Cashore at 416-526-4704 or Scott Anderson at 416-205-7515.