A Walmart worker was charged Wednesday with the brutal 1984 murder and rape of a 16-year-old Long Island girl — ending decades of mystery and speculation, Nassau County prosecutors announced.

Richard Bilodeau, 63, was arraigned on murder charges for the Nov. 10, 1984, cold-case slaying of Theresa Fusco, thanks to high-tech DNA testing by the FBI, authorities said.

“I never gave up hope,” Thomas Fusco, the slain teen’s dad, told reporters. “I always had faith in the system.

“For me, hearing that there was someone to finalize my daughter’s life will bring closure to me and my family,” he said. “It’s heartbreaking to go through this over and over again, but this seems like a finalization and I’m very grateful. Very grateful.”

Fusco, an aspiring dancer, left her job at the popular Hot Skates skating rink in Lynbrook on Nov. 10, 1984, and disappeared — and was found dead and naked nearby on Dec. 5.

“The DNA was taken from a vaginal swab,” Nassau County Assistant District Attorney Jared Rosenblatt said in court. “The defendant worked the overnight shift at Walmart in Suffolk County.

“When questioned, the defendant denied knowing her,” Rosenblatt told Judge Helene Gugerty. “He denied recognizing the pictures of her. When told about when the crime occurred, [he said], ‘Yeah, people got away with murder back then.”

Nassau County District Attorney Anne Donnelly said Fusco left the rink in tears after being fired before she went missing.

Donnelly said the teen’s body was found “buried beneath leaves in a wooded area a few blocks away from Hot Skates.”

Police said the bubbly teen had been raped, beaten and strangled, then dumped in the woods.

The grisly case horrified the quiet suburban community for months, until three local men — John Restivo, Dennis Halstead and John Kogut — were arrested and convicted in the teen’s horrific murder in 1986.

However, DNA evidence later cleared all three after they had served up to 18 years behind bars. They were freed in 2003, then sued and were awarded $43 million for wrongful prosecution, with the verdict later upheld on appeal.

Donnelly said investigators identified Bilodeau as a potential suspect in the decades-old case and trailed him.

Their break came in February, when the accused killer bought a drink at Tropical Smoothie near his Suffolk County home — and threw the cup into the trash, where cops retrieved it.

“The DNA from that straw, Richard Bilodeau’s DNA, was a match to the sample that was taken from Theresa’s body,” she said.

“He was 24-years old,” Donnelly added. “He was operating, according to him, a mobile coffee truck in Nassau County and he was living with his grandparents,” about a mile from the rink.

Asked about the earlier wrongful prosecution in the case, the DA maintained there is no doubt this time around.

“Science and DNA evidence doesn’t lie, period,” she said. “What happened in that case, I was not privy to. I was not the prosecutor on the case. But it’s 2025, and when you have a DNA match, 100% match, we got the guy.”

Defense attorney Daniel Russo denied his client was behind the grisly murder.

The charges bring long-awaited relief for the tragic teen’s parents.

On Wednesday, her father, Thomas Fusco, hugged a relative at the courthouse and whispered in her ear, “Now you go home and enjoy the rest of your life. Enjoy your daughter.”

“Everything that’s been said, I can tell you it’s been documented over the years, and I only loved her and miss her,” he told reporters. “She lives in my heart, as you can see.”

He held up a photo of Theresa.

Bilodeau was ordered held without bail pending a return court appearance on Nov. 21.