Gail Mark was killed in 1982. View Full Caption Family of Gail Mark

NEW YORK CITY — On the morning of Dec. 30, 1982, 28-year-old housewife Gail Mark was strangled and repeatedly stabbed by a man who wore her 3-year-old daughter's "E.T." mask.

The assailant locked the toddler in a nearby bathroom during the killing, leaving the girl just steps away from her dying mother.

When the first NYPD detectives arrived at the East 28th Street murder scene, they immediately eyed the woman's multimillionaire husband, Franklin Mark.

Gail’s mother and two sisters also suspected he played a role in the death, knowing he and Gail had a stormy marriage that was heading for divorce and a custody battle over their daughter.

Despite several investigations into the case focusing on Franklin over the last three decades and no other suspects emerging, he has never been arrested or charged, and Gail’s death remains unsolved.

Gail Mark's Mother Holds Family Photos of Her Slain Daughter. View Full Caption

But a recent revelation from Franklin’s own sister may prompt another look.

UPDATE: NYPD to Open Probe in Murder of Gail Mark

Last month, the sister, Ann Boyarsky, said in an affidavit that her brother played a central role in the murder.

“It was common knowledge in the family that my brother Franklin Mark was responsible for the death of Gail Mark in 1982,” Boyarsky said in the affidavit. “It was believed that he hired a hitman to kill his wife.”

Boyarsky made the filing as part of an ongoing legal fight with Franklin, where she accuses him of helping to loot at least $10 million from their frail and incapacitated mother in the years before her death.

Franklin was able to get away with the murder, Boyarsky said in the affidavit, because their mother shielded him from the police.

“I believe that my parents protected Franklin from prosecution and that they ironically became the victims of exploitation at his hands, other family members and their attorneys, in their last precious years of life,” she said in the court document.

Boyarsky declined to discuss her accusations with DNAinfo New York.

Franklin, who has repeatedly denied any involvement with his wife’s murder, also declined to comment.

But Gail Mark’s mother, Rita Fitzgerald, hopes NYPD detectives will seize on the words of Franklin's own sister and once more comb over the cold case.

“If you kill someone, you should pay the penalty,” Fitzgerald, 82, said. “I love my daughter very much, and she didn’t deserve to be killed.”

Gail Mark's murder made headlines in 1982 for its savagery and the shock that a 3-year-old may have heard her mother's killing.

Franklin, who is now 64, told detectives back then that he discovered his wife’s body lying on her back on the floor of their bedroom in their recently renovated East 28th Street duplex apartment.

After seeing his wife, he called police and freed their daughter, Dawn, who had been trapped in a bathroom.

Dawn and her father, Franklin Mark.

NYPD Det. Michael Abruzzi was one of the first investigators on the scene and headed the case.

“The body was laying at the foot of a king-sized bed,” Abruzzi, who is now retired, told DNAinfo New York. “She was wearing a nightgown pushed up to her waist. There was blood all over the place.”

Abruzzi said the murder looked like a crime of passion.

Gail had been stabbed so deeply with a 10-inch kitchen knife that the blade had hit bone and bent. A ligature was around her neck, showing that she had been thrown around.

But what caught Abruzzi’s attention the most was the pillow lying over Gail’s face.

“When someone knows the person who is murdered, after the rage is over, the suspect covers the face of the victim,” Abruzzi said. "It’s typical remorse."

The murder also didn’t seem like the result of a burglary gone wrong, the detective said. The apartment windows had bars on them, and there appeared to be no forced entry.

When Abruzzi spoke to Dawn at the hospital, she kept saying, “E.T. did it,” referring to the alien character from “E.T. the Extra-Terrestrial” movie, which came out in 1982.

Investigators found a mask of the character in the duplex. They were skeptical that a rushed burglar would bother to put on the mask, which belonged to the girl.

The mask was vouchered as evidence. Investigators also cut out a piece of the blood-soaked carpet. The swatch was given to the city’s Chief Medical Examiner’s Office to try to determine the time of the attack based on when the blood coagulated.

The crime scene also bothered investigators because it appeared staged.

A pool of blood that was 4 feet in diameter had collected on the bed, but Gail was found on the floor. That led police to believe she had been moved.

Her pocketbook was overturned on a table, and its contents were emptied. But police determined that nothing was missing.

Meanwhile, Franklin’s alibi didn't match his normal routine, Abruzzi said.

Franklin told police that on the day of the murder his wife was alive when he left his home at 6 a.m. to get a haircut before heading to his dad’s Manhattan garment business, Automatic Trimming Company, where he worked.

Franklin said he headed home from his office at 11 a.m. to meet a service man at his apartment when he discovered Gail's body.

Investigators knew Franklin was known for putting in long hours at his job. Leaving early was out of character for him, according to Abruzzi.

Adding to detectives’ suspicions was the cut they noticed on Franklin’s hand two days after the murder, when he came with a lawyer to talk to police, Abruzzi said. Franklin told investigators that the cut — which was starting to scab — came from an accident he had with a truck at work.

Investigators followed many leads, but they all were dead ends.

The apartment, which was in a building that Franklin owned, had recently undergone extensive renovations. Abruzzi said he personally fingerprinted 50 workers from a Brooklyn contracting firm that had done the renovations.

That didn’t lead anywhere.

Abruzzi also looked into a hitman angle. Again, nothing.

He also spoke with people who knew Franklin, including stewardesses who rented one of his apartments and would go out to dinner with him. But the interviews didn't break new ground.

Meanwhile, the blood work by the medical examiner’s office was inconclusive, making it impossible to corroborate or discount Franklin's timeline. And since DNA testing didn’t exist then, investigators couldn’t do much with the "E.T." mask.

The case grew cold.

In 2000, one of Franklin’s neighbors inquired about the case’s status, prompting detectives to take another look, law enforcement sources said.

Five investigators spent two years working the murder, scouring bars and restaurants that they believed Franklin patronized in hopes of finding a longtime employee who might have heard him talk about his dead wife.

They interviewed two stewardesses who knew him, sources said. But their information didn’t move the needle on the case. One flight attendant told the detectives that he made "incriminating" statements about his wife while the other described him as a nice guy, according to sources.

The investigators also hoped that advances in forensic science, including DNA testing, would help them crack the case.

They planned on testing the "E.T." mask and the bloody carpet. But they found the mask had been destroyed at the NYPD property clerk's office six months after the murder, sources said. Meanwhile, the carpet had gone missing from the medical examiner’s office.

The detectives even interviewed Franklin at one point at his office in his garment busines. But he didn't stray from his previous statements. He knew the investigators didn't have proof — and he seemed to almost toy with them, sources said.

“We were close, but ultimately decided there was not quite enough," recalled Daniel Bibb, the former Manhattan prosecutor handling the Cold Case probe.

Rita Fitzgerald said that Franklin never fit in with her family.

“I would say that we tolerated one another,” Fitzgerald said. “When he became family, he became family. It wasn’t my choice.”

Franklin was raised in Queens and came from money. He owned property around Manhattan and drove Cadillacs. He preferred to eat out rather than enjoy a home-cooked meal, Fitzgerald said.

Gail was raised in Queens and Brooklyn and endured a tough childhood with an abusive father, according to Fitzgerald.

Rita described Gail as beautiful, smart and troubled. She said Gail received a scholarship to the Academy of the Sacred Heart of Mary high school on the Upper East Side, but her daughter dropped out and ran away from home as a teenager.

Gail eventually retuned to New York and briefly attended nursing school. But for a time she worked as a call girl in Manhattan, according to her mother and her sister, Joan Fitzgerald.

Neither Rita nor Joan could remember exactly how Gail and Franklin met, but said the call-girl job could have been the connection.

The couple wed in 1977.

Rita and Joan both said it wasn’t a marriage made in heaven. The rocky relationship was punctuated by fights with each one threatening to leave with their daughter. There was talk of divorce.

Rita said Gail visited her with Dawn the night before the murder, complaining that she and Franklin had had another fight. Rita pleaded with Gail to spend the night at her place, but her daughter decided to go home.

Joan said she told Gail a week before the murder that she was endangering herself by staying with Franklin.

“I said, ‘You are going to end up on the front cover of the New York Post.’ And she laughed,” Joan recalled. She said that she learned of Gail’s fate from reading an afternoon newspaper on the day of the murder.

Franklin, who owns a townhouse a block from Gracie Mansion and a summer home in Atlantic Beach, L.I., re-married and had three other children, records show.

Dawn, who is now 36, declined to comment for this story. She is married, has a child and works as an administrative judge for the New York Labor Department. Records show she owns a four-family brownstone in Carroll Gardens, which she bought for $2.16 million in 2012.

Rita, who lives in Midtown, said that she’s never recovered from her daughter’s death.

“I saw a psychologist for about four years,” she said. “It still affects me adversely.”

Joan, a 58-year-old waitress who lives in TriBeCa, said she’s moved on with her life, managing not to think about her sister every day.

For the Fitzgeralds, the loss went beyond Gail. After the funeral, Franklin prevented Rita from seeing Dawn, her only granddaughter.

Rita sued for visitation rights as a grandparent, but when she won a judgment after a costly legal battle, she still never got to see the girl.

After Franklin lost in one family court, he moved to New Jersey, forcing Rita to sue again. Rita said by then she was facing eviction and didn’t have the means to pay for a lawyer.

“The fact that Franklin wouldn’t let me see my only grandchild really broke me up,” she said.

Franklin’s relationship with his own siblings isn’t any better than the one with his former in-laws, court records show.

He and his two sisters, Ann Boyarsky and Sharon Levine, have been fighting over the $23 million estate of their mother, Marcia Mark, since she died in February 2014.

Boyarsky and Levine claim that Franklin and the now-grown Dawn took advantage of their mother, who had suffered multiple strokes and had cognitive deficits.

The sisters said in court filings last month in Manhattan Surrogate’s Court that Franklin, Dawn and their lawyer, Mitchell Lapidus, coerced Marcia to give Dawn at least $10 million in gifts during the last four years of her life.

Gail Mark

The sisters also accuse Lapidus and Franklin of getting Marcia to change her will in 2010. Marcia’s new will left $8 million to the United States Holocaust Museum in Washingon, D.C., and the remainder of her estate to Dawn.

Boyarsky filed a Sept. 15 affidavit about Gail’s murder to persuade a judge to allow their lawyer, Jason Stern, to depose Lapidus and ask if Franklin ever spoke to him about the unsolved case.

“The court should require answers to questions about this criminal history and the role of family members and their attorneys,” Stern wrote in a filing last month.

“Alleged criminal activity resulting in the death of a distributee is certainly something that would effect family relations, with which the court should be concerned.”

CORRECTION: An earlier version of this story misstated the name of Franklin Mark's father's garment business. It was called Automatic Trimming Company, not Helvetia Sewing Machines Sales Corp.