What led a Cajun millionaire to brutally stab his British wife?

What could have happened to a Cajun millionaire-turned-English gentleman to lead him to murder?

Murder at the Manor 41:52

When Richard Vernalls, a reporter for The Worcester News in the British midlands, got that call that someone had died on Feb. 1, 2010, he knew this story was going to be big.

"Whenever we get a fatal we'll always go out to the scene," he told Richard Schlesinger.

The fatality was in the middle of a neighborhood with very rich residents and a very rich history.

"Former company executives... The great and the good," Vernalls explained. "It used to be like a Catholic seminary, for training priests."

But it wasn't just what happened or where it happened that made this crime so unusual.

"The question, the key question is always the why of it. Why would you do that?" Vernalls said. "So you have to find out the back story, you have to find out about the character of that person."

"I got a call from a reporter from England... Asking me if I was the guy who had represented Harold Landry in the past," said Pat Fanning.

Fanning was the right guy to call. Of course, he wasn't just Landry's lawyer. He was also his friend, despite the shooting.

"And you'd still hang out with him? Schlesinger asked Fanning.

"Sure, why not?" he replied. "He didn't kill any friends of mine."

They even had vacation homes in the same condo in Mexico. And it was there that Fanning met Landry's new bride, Lucy, in 2002.

"That was sort of an eye opener," said Fanning.

Fanning quickly noticed the somewhat odd nature of H. and Lucy's relationship. When they came to Mexico, the newlyweds were not alone.

"He came with the new bride, her son, the baby daddy and himself on vacation together," he explained. "She seemed more interested in spending time with the son's daddy than she did with H. And so I was like, this is just kind of weird."

But there they all were -- including the ex-lover, living it up and Landry was paying for everything.

"This did not seem to you to be the ideal marriage? Schlesinger asked Fanning.

"I usually don't bring my wife's old boyfriends on vacation with us," he replied.

H. didn't seem to mind. And in fact, things went pretty well for Mr. and Mrs. Landry, at least at first.

They lived in that house not far from the village of Pershore, where time is marked by the bells of a medieval abbey.

But time had started running out on the marriage just seven years after it began. Landry's friend, John Blakeman, visited only months before Lucy was killed.

"They were arguing at night," he recalled. "...as they began drinking, and the day wore on, they just -- began clashing."

But, over time, it wasn't just clashing that hurt the marriage; it was also cheating. Lucy took a new lover.

Landry's friend, Wanda Richardson, says it was hardly a secret.

"I'm sure she knew I knew," Richardson said. "A big part of this breakup was this other man."

Landry confided in his friend, Helen Knifton.

"He was very, very upset about it," she said. "He felt he failed in many ways."

"He began to feel somewhat out of control," Richardson said. "He said, 'We just won't ever be the same. ...She had someone else and that's the way it was going to be."

His name: Gareth Jenkins. Lucy knew him from high school and they reconnected on Facebook. But before long, H. began to suspect that their relationship went well beyond an innocent online poke.

"He would go to bed and Lucy would stay up hours past him online. He said, 'You know? I should've seen it. I should've seen something was going on,'" Richardson said. "He was in a bad place."

Landry decided to leave England for awhile and go to his place in Mexico to let things cool off. It might not have been the best move.

"He didn't know that she was going to move the boyfriend into the big house," said Fanning.

Harold Landry was furious, but his friend, John Blakeman, says H. still tried to save the marriage.

"He would have done anything and everything, including forgiving what is hard to forgive -- to keep the marriage together," he explained.

Lucy had made up her mind... she wanted out.

"He was crying, he was upset," said Richardson.

His friends say Landry was devastated, but it turned out that once Lucy took a boyfriend, H. found a girlfriend. Pat Fanning thought Landry was prepared for what would come next.

"He said, 'You know, I got a grip on this. I'm gonna go back and we're gonna get a divorce. She's not living in the expensive house we're in now ... She's gonna downgrade to something that is acceptable, but not the style we're in now,'" said Fanning.

Landry headed back to England in the fall of 2009. The marriage was effectively over and the fighting over the terms of the divorce was just beginning.

"He seemed to be encountering some difficulty with her with that notion that she was gonna [laughs] have to step down. I think she thought she was gonna get the house and the cars and everything and he was just gonna leave. And she was gonna keep the baby and all of his things," said Fanning.

Lucy, though, was preparing for the possibility of leaving with her children.

And if Lucy ever loved H., even after everything she knew, by February 2010, she felt very differently. And the divorce got even uglier. Lucy and H. kept arguing over money. She demanded he pay for an apartment for her and Landry agreed.

"She took the money that he gave her for an apartment and hired the best divorce lawyer she could get. And she played him," said Fanning.

It all came to a head on Feb. 1, 2010. That's when Lucy posted that last note on her Facebook page: "I've never hated someone as much as I hate someone now."

Lucy was talking about H. And less than an hour after she wrote those words, Lucy and Harold Landry had their final fight... with the children in the house.

And now, charged with Lucy's murder, Harold Landry is about to face a British jury at trial.