Victor Panebianco, 32, of King, North Carolina, pleaded guilty on Tuesday to first-degree manslaughter for knifing Christopher Millwater, 52, twice through his heart and lungs at a parking lot near Stony Brook Yacht Club on Nov. 10
.
Millwater’s ex-girlfriend, 33-year-old Kacy Corso, and Panebianco plotted to drive from their North Carolina apartment to Long Island to ambush him outside the yacht club where he was known to hang out
.
Corso had posted repeatedly about Millwater online.
In a Facebook post from the summer, a user under the name Kacy Corso wrote: “Whoever knows Christopher Millwater he is a grave robber”
.
The twisted couple pulled into the same lot as Millwater, before Panebianco exited the vehicle and approached the victim
.
After Millwater saw Panebianco, he tried to flee the parking lot, but Corso crashed into his car to stop him
.
Millwater understood his danger in an instant.
Millwater, of Selden, looked into Panebianco’s face and uttered the chilling last words, “You’re stabbing me?” and screamed as the maniac pushed a knife through his organs
.
Corso witnessed the attack and egged on her new boyfriend, telling him, “don’t believe him, don’t let him fool you”
.
The violence did not end with the stabbing.
Panebianco then heartlessly kicked the mortally wounded Millwater in the head before climbing back into his vehicle and fleeing the scene
.
The couple drove back to their shared apartment in North Carolina, where they were arrested days later by the Stokes County Sheriff’s Office
.
The Suffolk County Police Department uncovered the bloody scene after receiving a 911 call about an unconscious man on the ground of the parking lot by the upscale yacht club around 3:40 a.m.
The history between the two men was bitter.
Millwater and Corso had been involved in a romantic relationship, but they eventually split, and she grew increasingly hostile toward him
.
Corso regularly slammed her ex in a series of nutty social media posts — warning him not to contact her and calling him a “grave robber”
.
She had moved from New York to North Carolina, where she worked as a DoorDash and Uber driver
.
Yet she did not stay gone.
Investigators determined that Corso, who previously lived in Setauket and recently moved to North Carolina, traveled back to Long Island earlier this month with Panebianco to confront Millwater, and Corso knew Millwater would be in the parking lot
.
Panebianco’s guilty plea marks a dramatic shift from the murder charge he initially faced.
Panebianco is slated to return to court for sentencing on Sept. 22, where he is expected to be sentenced to 25 years to life in prison
.
His ex-girlfriend Corso has already moved forward with her own plea deal.
Kacy Corso, 34, of East Setauket, changed her original plea of not guilty during a court appearance Wednesday
.
Corso pleaded guilty to charges of manslaughter and hindering prosecution over the November 2025 stabbing death of 52-year-old Christopher Millwater
.
In the courtroom, Corso was asked the crucial question.
“What was the plan?” the judge asked. In low tones, the woman replied: “There was no plan.”
During her plea hearing, she reportedly said it was only her intent to “cause serious physical injury” to her ex-boyfriend
.
Yet her attorney attempted to minimize her involvement.
“She accepted responsibility,” defense attorney Christopher Gioe said outside the courtroom building in Riverhead on Wednesday
.
Her defense attorney, Christopher Gioe, told the outlet that she “accepted responsibility” and “had a very limited role in what happened in this case.” Corso was facing 25 years to life
.
She agreed to cooperate with prosecutors against Panebianco in exchange for the reduced charge.
Kacy Corso, 34, received the offer of a reduced charge in exchange with cooperating with prosecutors against her codefendant, Victor Panebianco, whom she said chased down Christopher Millwater, 52, of Selden, and stabbed him to death Nov. 10
.
Prosecutors are pushing for a lighter sentence as a result.
Prosecutors are likely to push for a seven-year sentence for Corso because she agreed to fully cooperate with the state’s case against Panebianco
.
In the viral moment that launched the entire investigation,
Corso positioned her car in front of Millwater’s car, Panebianco exited the passenger side of Corso’s car and approached Millwater’s car, Millwater drove around Corso’s car and towards the exit of the parking lot, and Corso then drove her car into his vehicle
.
Panebianco chased after him, swinging an object, and Millwater asked Panebianco, “You’re stabbing me?” and screamed for help and the police
.
Video shows Panebianco caught up to Millwater, and while Millwater was on the ground, Panebianco allegedly threatened to kill him and yelled at him to stay away from Corso, and Corso can also be heard yelling at Millwater, as Millwater lay motionless on the ground, Panebianco allegedly kicked Millwater in the head
.
The Suffolk County District Attorney’s office acknowledged the gravity of Panebianco’s actions.
“The defendant’s guilty plea does not take away the pain of the loss that Christopher Millwater’s friends and loved ones have endured,” District Attorney Raymond Tierney said in a statement. “However, his admission of guilt spares them from enduring a painful and difficult trial while holding Victor Panebianco fully accountable for this heinous killing,” Tierney added
.