Within a 13-minute window on April 15, 2004, Endres, a mom and owner of a hair salon in Cumming, Georgia, suddenly disappeared, leaving behind an uneaten lunch and a car that was parked at an unusual angle. Authorities have followed many leads over the years, but they still don't know what really happened to Patrice Endres that day. Here's what they do know about the case:

Police have narrowed down Endres' disappearance or possible abduction to a 13-minute window.

In the episode, Patrice Endres' son, Pistol Black, explains that his mom showed no signs of distress when she dropped him off at school that morning, unaware that it would be the last time he ever saw his mom alive. At 11:37 a.m. that morning, Endres answered a phone call from a client looking to reschedule their appointment. At 11:50 a.m. another call came in, but she didn't answer.

What happened in between those two phone calls remains a mystery. When authorities arrived at the scene, they found Endres' uneaten lunch and money missing from the cash register, but no other signs that there had been some sort of struggle. They did discover another oddity, though: Her car was moved and parked in front of the entrance to the salon at an unusual angle. Her clients say her usual parking spot was on the side of the shop, not the front.

Patrice Endres remained missing for over a year until her remains were discovered in a wooded area in December 2005.

Authorities discovered all of Patrice's remains near a church in Dawson County, Georgia, when two men called the cops after spotting a human skull on the ground. The church was about 10 miles out from her salon.

The one item police didn't find in the salon or at the wooded area is her wedding ring, which they believe may lead to a clue about what happened that day. The ring features a marquis diamond center stone and two bands soldered together. Law enforcement hopes someone will recognize the ring and lead them to the person that may be responsible for Endres' death.

Police have followed many leads, but none of them had led to arrests or an official account of what happened the day of Patrice's disappearance.

Convicted serial killer Jeremy Jones confessed to the kidnapping and murder of Endres, but in 2005 recanted his confession after admitting that he had lied to get better food and extra jail visitation and phone privileges, according to Tulsa World .

A number of other false confessions and misleading tips have plagued the case, but police have held on to one promising tip. Two independent witnesses claim they saw a small blue car in front of Endres' shop at 11:45 a.m. the day she disappeared. They both say another person was standing in front of the shop with her, and one recalls an odd scene where it looked like Endres and the other person had their hands on each other.

In the episode, a number of Endres' family and friends also say they're suspicious of her husband, Rob Endres, though he maintains didn't have anything to do with Endres' murder. Rob Endres had a bad relationship with Patrice's son, Pistol, and had the locks of the house where they lived changed just a day after her disappearance, according to the docuseries. Speculation about whether Rob Endres was involved have taken over forums on Reddit .

Authorities claim they do know some other aspects about the case that they cannot share with the public because it is considered guilty knowledge information, or information that only the perpetrator of the crime would know. Still, they need the public's help to solve the case.

Anyone with new information about the case should visit unsolved.com to submit their tip.