A 32-year-old Rockville man was sentenced to life in prison with no parole on Tuesday for breaking into a next-door couple’s home, stabbing them to death with a machete and fleeing on an Alaskan cruise.

“I don’t know what dark part of your soul caused you to do this. I’m not sure that anyone does,” Montgomery County Circuit Judge John W. Debelius told the attacker, Scott Tomaszewski.

He told Tomaszewski that he couldn’t think of any treatment or rehabilitation regimen in prison that would make him safe upon release. “I don’t think there is one,” Debelius said. “I come up empty.”

In the dark, early morning of May 10, 2015 — Mother’s Day — Tomaszewski cut open a screen at the home of his longtime neighbors. He first attacked Dick Vilardo, 65, as he slept, according to prosecutors. Dick’s wife, Jody, 67, fled toward the kitchen. Tomaszewski attacked her there. At some point, Dick Vilardo, stumbled down the hallway to try to save his wife, according to prosecutors, and was attacked again.

[Suspect in couple’s deaths on Mother’s Day wished all a happy holiday]

Scott Tomaszewski under arrest in Alaska.

Dick Vilardo suffered 42 cutting and stabbing injuries. Jody, his wife of nearly 40 years, suffered massive injuries to her neck.

Hours later, the Vilardos’ adult children — Andy and Katy, who had planned to meet them for a Mother’s Day gathering — went to check on them and discovered their bodies.

Detectives tracked down Tomaszewski on an Alaskan cruise with his family. They arrested him as he came off the ship for a day of whale watching.

Police did not determine a motive. He had burglarized a nearby house earlier, and while inside the Vilardo home he also took items.

But Tomaszewski was masked when he came to the Vilardo house and was armed with what prosecutors described as an 18-inch curved machete, similar in style to a Nepalese kukri knife. The attack on Dick Vilardo in his bed, rather than a spot that would indicate he had confronted a burglar, suggested to authorities that Tomaszewski intended to commit murder.

“This would be a textbook case of deliberate, premeditated murder,” Debelius, the judge, said.

Tomaszewski pleaded guilty in September to the killings.

An Eagle Scout at 13, he was raised in Montgomery County by two longtime cancer researchers at the National Institutes of Health. He graduated from high school but had trouble holding a steady job. He was living with his parents on the night that he slipped out for the attack.

His parents didn’t know what had happened, even as they left for the airport to fly to their cruise, officials said.

Tomaszewski had suffered from seizures. One of them led to a car wreck, which led to a brain injury. Another caused him to fall into a hot tub, nearly drown, and go into a medically induced coma for five days.

Tomaszewski’s attorney, John Kudel, had his client evaluated by doctors to try to determine whether there was a connection between the old injuries and deep mental illness but, after their findings, chose not to pursue a defense that Tomaszewski was legally insane at the time of the killings.

“There’s no medical explanation from these doctors who have looked at him and seen him,” Montgomery State’s Attorney John McCarthy said in court, “other than we may be looking at evil.

In court Tuesday, Tomaszewski spoke for 10 minutes.

“I’m an introvert. I like to keep to myself for the most part,” he said, saying that being around too many people fills him with anxiety. “I can’t stand attention or confrontations, which makes the actions that put me here today so abhorrent to my natural self.”

He also said: “I can’t do anything to bring Dick and Jody back to life. And despite how ashamed and disgusted I am with myself, no amount of words or apologies will help console their family.”

Tomaszewski said he was seeking psychological help and had been about to admit himself into a treatment program. “I didn’t realize how imperative my needing immediate help was,” he said.

When the judge spoke, he cited Tomaszewski’s phrasing that the couple had lost their lives, arguing that such language showed Tomaszewski had not accepted that he had killed the Vilardos.

“You know what, whether now or whether at some point in your life, you need to own this thing,” the judge said. “These people weren’t lost. These people were murdered, and they were murdered brutally and viciously.”