According to Irish police, a love triangle led to a brutal murder in the rural farmland near County Tipperary. (Niall Carson/PA Wire)

He slipped away as the dawn sunlight was just beginning to burn at the edges of the rural farmland outside County Tipperary, Ireland. As always, Mary Lowry waited for the reassuring sound of the silver Citroen van thumping over the gate and away her dairy farm back.

Her boyfriend, Bobby Ryan, liked to leave at daybreak so that Lowry’s three young sons did not know he had stayed the night. Whenever she heard the car wheels crossing the barrier, the widow knew Ryan had made his exit unnoticed. She could then relax. But on June 3, 2011, Lowry waited and waited, much longer than usual, before she heard the van clunk off, the Irish Times would later report.

Ryan was a truck driver and weekend DJ known as “Mr. Moonlight” with two grown children. After leaving Lowry’s farm, the 52-year-old did not show that day for work at a quarry. His van was later found abandoned in a wooded area. According to the Times of London, when Ryan’s family learned the doors were unlocked, they knew something was wrong. Ryan’s DJ equipment was inside, and he would never leave it unprotected.

Pubs and shops were plastered with missing-person posters, but Ryan remained missing.

Then, on April 13, 2013, almost two years after Ryan was thought to have last driven away from Lowry’s farm, police found out that he had never left.

That afternoon, a dairy farmer working on Lowry’s land named Patrick Quirke discovered Ryan’s naked body at the bottom of a concrete slurry pit, a 10-foot-deep space used for animal waste and water. Ryan had been beaten to death with a blunt instrument. His skull, ribs and one leg were fractured.

“Somebody knows something,” the victim’s brother, John Ryan, told the Herald in June 2015. “Bobby didn’t jump into the tank of his own free will and put a slab on top of himself.”

After years of investigation, authorities would eventually announce that, like Ryan, his alleged killer was also closer than anyone realized.

This week, Quirke, 50, was put on trial for Ryan’s murder. In his opening statement, prosecutor Michael Bowman told the court that the crime stemmed from a complicated love triangle that boiled over into violence.

“It is manifestly clear to Patrick Quirke that he could not compete with Bobby Ryan for Mary Lowry’s affection,” Bowman said, according to RTE, Ireland’s public television network. “He could not compete with his love rival.”

Quirke has pleaded not guilty to the crime.

The defendant was considered one of the region’s best-known dairy farmers, the Herald reported in 2013. He also was intimately linked with Lowry’s family. As the Irish Times has reported, Quirke had been best friends with Lowry’s husband, Martin. His wife, Imelda, was also Martin’s sister.

In 2007, Martin died of cancer, leaving behind his wife and three children, the Thurles Information reported. The widow was also left with the farm, a series of grass fields bright as emeralds and sloping hills situated between the towns of Tipperary and Bansha. Quirke offered to lease 63 acres of the Lowry farm for his cattle.

According to prosecutors, the relationship between Quirke and his late best friend’s wife turned romantic in 2008. The two allegedly carried on a secret affair until 2010, when Lowry cut if off.

That August, Lowry met Ryan, the Irish Times reported.

The widow’s new boyfriend was popular throughout the area.

“Bobby was known the length and breadth of Tipperary from his work driving the lorry and working as a DJ. He was a lovable rogue,” his brother John told the Herald.

“Bobby had music in his heart and soul — Mr. Moonlight touched the hearts of many, set the lips laughing and the feet dancing,” the priest at his funeral would later remember, according to the Irish Examiner.

But prosecutors allege that Ryan, who was separated from his wife, also provided Lowry with something her clandestine relationship with Quirke could not — a “conventional open normal relationship,” prosecutor Bowman told the court.

Authorities allege it was the farmer’s fierce jealously that drove him to plot Ryan’s death, hoping that once Lowry’s new boyfriend was gone, his relationship with her would resume.

The romance did flare again after Ryan disappeared in June 2011, according to the Irish Times. But Lowry eventually broke it off again.

If Quirke killed his romantic rival, as authorities suggest, why would he lead authorities to the body?

As Bowman laid out in court this week, Quirke’s discovery of the body was allegedly a “carefully managed, orchestrated and staged” act to divert suspicion.

By April 2013, Lowry had decided to cancel the lease agreement with Quirke. The farmer would no longer have access to the land by July, and authorities say he worried that one day someone else might discover Ryan’s remains at the bottom of the slurry tank. Quirke allegedly staged the discovery to make authorities think he was not involved.

However, the prosecutor acknowledged that there would be “no smoking gun or act caught on CCTV” presented at the trial, RTE reported. Rather, Bowman argued that the circumstantial evidence all would point to Quirke.

The trial continues Thursday and is expected to go on for six weeks.

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