Fright Night turned really scary for Paris Hilton.
The party-hearty heirhead and her boyfriend du jour, Doug Reinhardt, were spotted in an apparent boozy grapple early yesterday — with him reaching from the back of their limo to put his hand around her throat in a move that stunned even jaded Sunset Boulevard denizens.
“She was mad,” said lensman Ramon Alves. “She jumped in the front seat and [Doug] was holding her around the neck saying, ‘Relax, relax.’ ”
Hilton, 28, and Reinhardt, 24, started out Halloween night sporting goofy, matching tooth-fairy outfits at a bash thrown by “Project Runway” glamour girl Heidi Klum and her singer-husband, Seal, in West Hollywood.
The pair then took off in a limo to The Roosevelt hotel in Hollywood for another round of partying.
At around 3:30 a.m., Paris & Co. left the Roosevelt, pouring into their limo for the ride home.
“You could see them chugging from a bottle inside the car,” said another witness.
But the action was just getting started.
At the corner of La Brea and Sunset Boulevard, the reality star’s cellphone was launched out the window.
The limo came to an abrupt stop, and a tipsy Paris stumbled out, peering up and down the street to find her phone as traffic — and pedestrians — came to a halt.
“She was staggering down the street, up and down,” the second witness said.
Failing to find her phone — it was later located and returned by a paparazzo — Hilton climbed back into the limo and began ranting at Reinhardt for throwing it out the window, the witness said.
She also started slapping and kicking as he grabbed her and tried to fend her off. His left hand had a firm grip on her throat, according to the witness.
“And the guy they were with was trying to block anyone from taking pictures,” the witness said.
“It got very physical. The limo driver was horrified!”
The incident was witnessed by several photographers.
On Friday, the socialite made an appearance on “Jimmy Kimmel Live” dressed in a sexy gingham get-up as Dorothy from “The Wizard of Oz” and Toto-ing her little dog along in a wicker basket.
Reinhardt, too, wore a Dorothy costume that night.
A call to a Hilton spokeswoman was not immediately answered. No police report was filed on the couple’s Halloween incident.