'Loud argument with Nick Reiner': Inside Rob Reiner’s final night at Conan O’Brien’s Christmas bash

While the Christmas party was a strictly formal affair, filled with guests in tailored suits and evening gowns, Nick Reiner reportedly ignored the dress code entirely. Witnesses state he arrived wearing a simple hoodie, a visual clash that immediately made him "stick out like a sore thumb" amidst the Hollywood elite, as per a report by TMZ.

Beyond his clothing, Nick’s demeanour reportedly caused unease among the attendees. Sources describe him as "roaming" the venue in his sweatshirt, appearing reserved and keeping entirely to himself rather than engaging in the festivities.

Despite the social nature of the holiday event, Nick reportedly did not mingle with other guests. His isolation was stark; he was seen wandering the party alone, creating a "ghostly" presence that some attendees found odd and out of place for such a gathering.

The silence he maintained with guests was broken by a volatile interaction with his father. Nick and Rob Reiner were observed getting into a "very loud argument" that was heated enough to be overheard by numerous bystanders, marking a public fracture in their relationship just hours before the murders.

Following the verbal altercation, Rob and Michele Reiner chose to leave the party. While the couple exited shortly after the fight, it remains unclear exactly when Nick left the premises or where he went immediately afterward.

The tension of Saturday night culminated in tragedy on Sunday when Nick’s sister, Romy Reiner, discovered Rob and Michele in their Brentwood home. Both had their throats slit, a brutal end that followed the previous night’s public dispute.

Upon finding the bodies, Romy explicitly warned police that her brother had been living with their parents and was "dangerous." Based on this information and the evidence at the scene, Nick was arrested, booked for murder, and is currently being held without bail.