The reason Conan O'Brien reportedly "stopped party guests" from calling 911 on Nick Reiner the day before Rob and Michele Reiner were murdered has been revealed.
The Hollywood icon, 78, and his wife, 70, were found dead inside their Brentwood home on December 14, both killed by knife wounds.
Their youngest daughter, Romy, discovered her father’s body around 3:40 p.m., unaware her mother had also been killed until paramedics found Michele elsewhere in the house.
Their 32-year-old son, who lived in the guesthouse on the property, was nowhere to be found.
He was arrested several hours later, about 15 miles away, and has since been charged with two counts of first-degree murder.
The killings came less than 24 hours after a disturbing confrontation involving Nick at a celebrity Christmas party hosted by Conan O’Brien.
Investigators have not offered a motive, but new accounts from party guests paint a troubling picture of Nick’s behavior in the final hours before the deaths.
.jpg_X7S3g7?tr=cr-378.0.934.731,f-webp,q-75)
Conan O’Brien Shut Down A Police Call During Explosive Fight
According to the Daily Mail, multiple attendees have alleged that Nick was involved in a heated and increasingly volatile argument with his father at O’Brien’s Los Angeles mansion on Saturday night.
The situation reportedly became so intense that at least one guest suggested calling 911. “They got in an argument, the father and son. It got so bad and loud someone wanted to call the police to report it,” one insider said.
The source claimed O’Brien intervened. “But Conan stepped in and said, ‘it’s my house, my party, I’m not calling the police.’ He talked them out of calling the police.”
Another guest confirmed the account, saying partygoers were alarmed by Nick’s mental state and discussed placing him on a mental-health hold.
“When the s**t was hitting the fan, somebody said we need to call the police. The conversation was about getting this kid put into a mental-health hold,” the second source said.
"Conan O'Brien stepped in and said, 'no, I don't want the police at my house'. It makes sense; who wants the cops showing up creating a scene?" the insider added. “But the argument between Rob and Nick was pretty intense.”
A source close to the Los Angeles Police Department said there were no 911 calls from the talk show host's home that night.
"I’m Petrified Of Him"
That same night, Reiner reportedly confided in friends that he feared his son. “I’m petrified of [Nick],” he allegedly said. “I can’t believe I’m going to say this, but I’m afraid of my son. I think my own son can hurt me.”
Those comments resurfaced at an impromptu memorial attended by Hollywood A-listers, where the details of the party were discussed.
One guest said several attendees were left in tears after hearing what Reiner had said. One representative later denied that the comments were made at O’Brien’s party.
TMZ previously reported that Rob and Nick had a “very loud argument” at the event, after which Rob and Michele left. The couple had reportedly brought Nick to the party to “keep an eye on him”.
Guests described Nick displaying antisocial behavior, including staring at people and repeatedly asking if they were famous.
“Nick was freaking everyone out, acting crazy, kept asking people if they were famous,” one source told PEOPLE.
Another witness said Nick interrupted Bill Hader during a private conversation: “Nick just stood there and stared before storming off.”
Mental health Spiral, Arrest, and Court Proceedings
Nick had a long history of substance abuse, including at least 18 stints in rehab and periods of homelessness.
He had reportedly been diagnosed with schizophrenia and was receiving treatment at a $70,000-a-month Los Angeles facility.
Weeks before the murders, doctors changed his medication, after which he "was out of his head,” a source told TMZ.
After the killings, investigators tracked Nick walking the streets, buying a drink, and briefly checking into a Santa Monica hotel. Staff later discovered a shower “full of blood,” a trail leading from the bed, and a window covered with bedsheets.
He is now being held without bail. His first court hearing was delayed because he was not medically cleared for transport, according to his attorney Alan Jackson.
When Nick later appeared in court, he wore a suicide vest and only spoke to say, “Yes, your honor,” while waiving his right to a speedy arraignment.
His next court date is scheduled for January 7, 2026.