The knife that was driven into the back of famed Toronto hairstylist Fabio Sementilli was literal — and figurative.

Now, nearly eight years to the day of a vicious murder, the woman cops say is the mastermind behind the slaying of the beloved 49-year-old Sementilli will go on trial for first-degree murder in Los Angeles.

That woman is Fabio Sementilli’s widow and the mother of two of his children: Monica Crescentini.

Fabio Sementilli and his wife Monica in happier times. INSTAGRAM
Fabio Sementilli and his wife Monica in happier times.Photo by INSTAGRAM

In earlier grand jury proceedings, Monica, 52, has been portrayed as vain, manipulative, sex-crazed, and greedy.

Sementilli — a vice-president for Wella — was stabbed to death on the patio of his posh Woodland Hills home while he enjoyed a glass of wine and a cigar on Jan. 23, 2017.

In the background, LAPD homicide detectives were peeling back the layers of a pungent onion that six months later led to Monica, her former porn star boyfriend, Robert Baker, and a third flunkie named Christopher Austin.

Monica Sementilli and her paramour, Robert Baker. He pleaded last summer to first-degree murder in connection with the death of her husband Fabio. She goes on trial April 2. LAPD
Monica Sementilli and her paramour, Robert Baker. He pleaded last summer to first-degree murder in connection with the death of her husband Fabio. She goes on trial in December. LAPD

Baker and Austin have already pleaded guilty. Baker has been sentenced to life in prison while Austin copped to second-degree murder last week and is expected to testify against Monica.

Previously, Baker said his playmate had nothing to do with the murder, but facing down the barrel of a life sentence at San Quentin can change a person’s mind.

Jury selection is slated to begin on Tuesday.

Monica Crescentini, 49, and her convicted sex offender boyfriend Robert Louis Baker, 58, face their murder trial in October.
Monica Crescentini, 49, and her convicted sex offender boyfriend Robert Louis Baker, 58, were charged in the death of Fabio Sementilli.

The script for this tragedy reads part porno, part film noir, and the case has even attracted the attention of 48 Hours, Dateline, and others. On the line was Fabio’s $2.3-million insurance policy.

Monica allegedly provided Baker with instructions via email on how to torpedo the home’s CCTV and told him when Fabio would be alone. She then went shopping to allegedly construct her alibi.

But Baker cut himself during the attack, leaving behind his DNA, which detectives linked to his underage sex beef in the early 1990s.

That led cops to a lurid tale that drove her legal team to try to keep the sensational, sexually-driven elements of her indictment under lock and key. The judge said nope.

Monica and Fabio Sementilli. Cops say she conspired with her lover to murder the beloved hairstylist. FACEBOOK
Monica and Fabio Sementilli. Cops say she conspired with her lover to murder the beloved hairstylist. FACEBOOK

Among the bon mots:

— As Sementilli’s devastated family was grieving, his widow was having sex in a Las Vegas hotel room with Baker — who even showed up for the wake.

— Monica Sementilli was so desperate to get her hands on her share of her late husband’s insurance policy she called detectives about it constantly.

— Baker the lothario allegedly stroked his much-married gal pal’s ego by telling her she was beautiful and sexy.

— Testimony also revealed the accused murder mastermind flirted frequently with other men besides Baker.

“This is her in Las Vegas …. Here she is dancing, celebrating Robert Baker’s birthday. She’s right behind him taking selfies and you’ll see what was going on in reality … sometimes a picture really does tell it all,” prosecutors said, adding she is “an Academy Award-winning actress.”

The next day, Monica was allegedly making out with her convicted sex offender beau in a bar. And when she went outside for a cigarette, the prosecution alleges the new widow made a play for the bouncer.

Beloved Toronto hairstylist Fabio Sementilli with his mother Maria
Beloved Toronto hairstylist Fabio Sementilli with his mother Maria, who has since died. SUPPLIEDPhoto by SUPPLIED /SEMENTILLI FAMILY

One of her friends, Sheila Salehian, testified to the grand jury about Monica’s newfound lust with Baker.

“I think ‘satisfied’ was one of the words. I think she meant sexually, like she was exploring things with him,” Salehian said.

Baker reportedly told Salehian that she was “very demanding” in bed and he was burning out.

And then there was the insurance payday. Monica was allegedly pissed it was taking so long to have her palm greased.

She asked detectives: “Why haven’t you cleared us? When are you going to clear us? I need this money. Oh my God, I’m going to have to sell the house, I’m going to have to fire my housekeeper, I’m going to have to fire the gardener, I’m going to have to fire the pool man.”

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