As a Halloween party in an upscale neighborhood gets out of hand, neighbors call 911 saying there are too many cars and drunk teens in the neighborhood.

As Preston Lord and his friends leave the party, one of Lord's friends has a necklace stolen by another group of teens. A fight breaks out when Lord tries to get the necklace back. He is beaten by a group of teens who knock Lord unconscious and kick him while he’s on the ground. Witnesses recount seeing the attackers “hump” Lord and someone in a white suit returning to stomp on Preston Lord, still unconscious in the middle of the street.

As Preston Lord lays unconscious on the pavement, friends determine his heart has stopped and other partygoers perform CPR until police arrive and take over. Lord is taken by ambulance to Chandler Regional Hospital, then transferred to Phoenix Children's in extremely critical condition with a severe brain injury. Preston Lord succumbs to his injuries.

For those involved, Lord’s death is fodder for social media, some trying to figure out how to cash in on the reward money offered for information about what happened.

The suspects discuss the fight over Snapchat, with one of the messages reading, "My mom wants in on the $10K.”

These messages are some of the first real clues police begin to follow.  A tipster notifies police that Talan Renner admitted to a friend that he threw the first punch, and Owen Hines told a friend “he only kicked him in the stomach.”

Nearly all the witnesses point out Treston Billey and Dominic Turner as aggressors due to their distinct costumes that night. Turner wore all black, while Billey donned a white suit.

Using the suspects' digital media, investigators find Taylor Sherman, who admits to taking a video of Preston as he is unconscious on the ground and sending it out on Snapchat. Talyn Vigil also sent a message reading, “I hit a kid and this kid fell, hit his head. Then they kicked his head in the ground, then I got word he died so idk.”

The day Preston Lord passes away, Talan Renner’s millionaire father, Travis Renner, goes to work trying to cover up the teen’s involvement. Renner and his business partner allegedly hand out NDAs and push a story that despite Talan Renner having thrown the first punch,

Talyn Vigil was truly to blame for Lord’s death. Renner tells the school his son is being bullied, and whisks Talan away to his $800,000 golf club cabin in Show Low, Arizona for a week while Talan’s hands heal from the fight.

Meanwhile, Talan Renner brags to friends on Snapchat, “I got in a fight, a big group fight, and I accidentally killed a kid. I guess I’m just too strong.”

Joining Nancy Grace Today:

• Jeanna "Gina"  Pignatiello  - Neighbor who called 911; Instagram @JPignatiello 
• Ray Giudice – Criminal Defense Attorney in Atlanta, GA; X: @raygiudice
• Dr. Shari Schwartz – Forensic Psychologist (Specializing in Capital Mitigation and Victim Advocacy); Author: “Criminal Behavior” and “Where Law and Psychology Intersect: Issues in Legal Psychology;” X: @TrialDoc" 
• Julie Lewis – President & CEO, Digital Mountain, Inc.  
• Dr. Jan Gorniak – Medical Examiner, Clark County Office of the Coroner/Medical Examiner (Las Vegas, NV), Board Certified Forensic Pathologist
• Alexis Tereszcuk - CrimeOnline.com Investigative Reporter, Writer/Fact Checker at Lead Stories; X: @swimmie2009