Holiday parties, family turmoil, and two brutal murders. The more we learn about Rob and Michele Singer Reiner's final moments, the more shocking this whole case becomes. With an active investigation into their killings ongoing, the timeline of events continues to evolve. From who found them and how to what time they were likely killed. Read on for the complete breakdown... Related: Kimmel BLASTS Trump's Comments About Murders Of Rob & Michele Contents [hide] 1 Conan O'Brien's Holiday Party 2 Bill Hader Tiff & 'Crazy' Behavior 3 Nick & Rob Argue 4 NEW: When They're Killed 5 Nick Flees To Santa Monica 6 Romy Discovers Parents Dead 7 Nick MIA 8 Nick Arrested 9 On Suicide Watch 10 Securing A Powerhouse Lawyer 11 Nick Misses Court Hearing 12 Charges Announced Conan O'Brien's Holiday Party It all started like normal. Rob, Michele, and their son Nick attended Conan O'Brien's annual Christmas party on Saturday night, December 13. To many, Nick - who has struggled with mental health and addiction issues - seemed out of place at the formal gathering since he showed up in a hoodie and mostly kept to himself... until he didn't. Bill Hader Tiff & 'Crazy' Behavior Per NBC News, Nick interrupted a convo Bill Hader was having with two others. Bill tried to politely tell Nick to move along since the conversation was private, which didn't sit well with the 32-year-old. He eerily stood still and stared at the actor before "storming off." Us Weekly sources also claimed Nick was acting "creepily" and "going up to people at Conan O'Brien's party, asking people if they were famous." Two People sources doubled down: "Nick was freaking everyone out, acting crazy, kept asking people if they were famous." Nick & Rob Argue Also at the party, TMZ insiders alleged Nick and Rob got into a "very loud argument." It's not clear what they were talking about, but lots of folks overheard them bickering. Rob and Michele left the event soon after. NEW: When They're Killed Now, according to new intel on Tuesday, this is likely when tragedy struck. Everything changed once they left Conan's bash. Los Angeles County District Attorney Nathan J. Hochman revealed in a press release on Tuesday that the couple was murdered in their Brentwood home "in approximately the early morning hours of December 14," likely before dawn, which would be around 6 a.m. local time. Nick Flees To Santa Monica Nick then fled to Santa Monica and checked himself into The Pierside Santa Monica hotel at around 4 a.m. on Sunday with his own credit card, eyewitnesses told TMZ. Witnesses said he seemed "tweaked out," but they didn't notice any visible signs of violence on him. He booked a room for one night and did not formally check out. Sometime later on Sunday, housekeepers were doing their usual rounds when they discovered his shower was "full of blood" and there was blood on the bed. The windows were also covered by bed sheets. So scary. Investigators showed up to the hotel on Monday to interview employees and collect evidence. Romy Discovers Parents Dead On Sunday afternoon, Rob and Michele's massage therapist showed up to their home for a scheduled appointment. When they couldn't get in through the gate or get in touch with their clients, they called their 28-year-old daughter Romy. A source told the New York Times she arrived to the property with a roommate. Romy went inside to check on her parents, and that's when she discovered her dad's body. She quickly fled the terrifying scene - without seeing or realizing her mom was also dead (a paramedic later informed her). Outside, her friend called 911. Authorities arrived at around 3:40 p.m., and according to law enforcement sources, they determined the couple had been killed approximately 12 hours before discovery because of the state of rigor mortis they were in, among other signs. According to reports, the 78-year-old director and 70-year-old film producer's throats were slit and they were stabbed, allegedly with a knife. TMZ sources described the bodies as looking like they'd been "butchered" by a "mad man." Horrifying. Nick MIA Romy told authorities that her brother lived on the property (in their parents' guesthouse), but he was not on scene when she arrived. According to TMZ reports, she told cops she suspected he could have committed the killings (though the NYT's insider claims she only said he lived there). He was nowhere to be found and was unaccounted for for nearly six hours. Nick Arrested Finally, at about 9:15 p.m. on Sunday night, the Being Charlie writer was arrested. Cops tracked him down near Exposition Park by USC in Los Angeles. In security footage obtained by NBC News, he was seen walking into a gas station, purchasing a drink, and heading down the street. Police cars drive by him, then turn back seconds later, swarm him, and arrest him. Nick did not resist arrest. On Suicide Watch Nick was taken into custody. Initially, his bail was announced at $4 million - however, that was quickly revoked. He's being hel