Sharon Tate's younger sister, Debra Tate, has lashed out against the new film about her sister's 1969 murder starring Hilary Duff.

In a new interview with People, Tate calls the film "classless" and "exploitative."

The film, titled "The Haunting of Sharon Tate," stars Duff as Tate's famous sister, Sharon.

“Had the incredible opportunity of playing Sharon Tate the past two weeks in an independent movie. She was an amazing woman and it was a true honor," Duff captioned a recent Instagram photo of herself in full Sharon Tate hair and makeup.

But Sharon's younger sister, who was 16 when the 26-year-old actress and model was brutally murdered by Charles Manson's followers, has an issue wiith the film.

“It doesn’t matter who it is acting in it – it’s just tasteless,” Tate said. “It’s classless how everyone is rushing to release something for the 50th anniversary of this horrific event," Tate explained.

Another major issue Tate said she had with the film was the movie's dream scene where Sharon has a premonition that she and her celebrity hairstylist ex-boyfriend, Jay Sebring, would die after having their throats slit. The dream is apparently used to set up the murders as the premise for the film.

charles manson

Charles Manson. (AP)

But Tate called the dream fabricated and "tacky."

“I know for a fact she did not have a premonition — awake or in a dream — that she and Jay would have their throat cut,” she told People. “I checked with all of her living friends. None of her friends had any knowledge of this. Tacky, tacky, tacky. It’s a total fabrication.”

Sharon's friends, who had dinner with the actress prior to the murders, were also killed at the house she shared with director Roman Polanski.

Sebring, Abigail Folger, Wojciech Frykowski and Steven Parent were found stabbed to death at Tate's home along with the young actress, who was married to Polanski. Tate was eight-and-a-half months pregnant with their first child when she was killed.

Debra Tate Reuters

Debra Tate, sister of slain actress Sharon Tate, reacts after convicted mass murderer Charles Manson was denied parole at his 12th parole hearing for the 1969 Tate-Labianca murders, April 11, 2012. (Reuters)

“It would have been nice if someone had contacted me,” Debra Tate said explaining that she owns the rights to her sister's likeness.

After being convicted of the murders, Manson was sent to California’s Corcoran State Prison to serve time for nine life sentences. The infamous cult leader and killer died at the age of 83 on Nov. 20, 2017.

Debra Tate said on the day of Manson's death she received a call from the prison to inform her of the news. “I said a prayer for his soul.”