It's one of the most notorious unsolved murders in recent memory and certainly the most notorious crime in the state of Colorado. More than 20 years ago on Christmas day, a child beauty queen named JonBenét Ramsey was found murdered in her Boulder, Colorado home. Now, a new special on A&E will explore the hunt for her killer. 

If you need a quick refresher on the case, here's everything you need to know about the JonBenét Ramsey investigation, from how she died to why her family continues to face suspicion despite DNA evidence supporting an intruder carried out the crime.

How did JonBenét die?

On the morning of December 26, 1996, JonBenét's mother, Patsy Ramsey, said she found a three-page ransom note on the staircase leading from the kitchen, demanding $118,000 — nearly the exact amount John Ramsey had received as a bonus that year. Though the note said not to call police, Patty did, a little before 6 a.m. Police arrived within minutes of the call and found no signs of forced entry.

Hours later, at 1 p.m., a detective on the scene instructed John and a family friend to search the house for anything that looked strange. They went to the basement where John opened a latched door police did not open earlier that morning and found the body of JonBenét. She had duct tape over her mouth and was bound at the wrists with nylon cord. There was also a cord around her neck. An autopsy revealed she had died from strangulation and a skull fracture, but no obvious signs of sexual assault. However, there was evidence her vaginal area had been wiped with a cloth and evidence of a past vaginal injury.

Why were her parents suspects and how were they cleared?

Suspicion surrounded the Ramseys from the jump for several reasons. First of all, any time a murder occurs in the home, the people who live there are the most likely suspects, and with no obvious signs of forced entry, the circumstances didn't suggest a home invasion to detectives. 

The note and ransom amount also raised red flags with investigators. The letter was lengthy and written on a notepad that was in the home, which suggests they took some time penning it. There was also a practice draft. Investigators found it unlikely that a would-be kidnapper or murderer would linger at the crime scene long enough to write such a long note. 

It was also suspicious to police that the amount demanded in the note was almost identical to the bonus John received.

However, forensic investigators extracted DNA from a blood sample in JonBenét's underwear in 2003 and found genetic markers that did not match anyone in the Ramsey family A new analysis in October 2016 found genetic markers from two people other than JonBenét in the original sample. 

This finding prompted Boulder County District Attorney Mary Lacy to write a letter of apology to the Ramsey family, stating, "I am very comfortable that our conclusion that this evidence has vindicated your family is based firmly on all of the evidence."

Where are the Ramseys now? Are John and Patsy still alive?

John Ramsey is alive and as of 2017 was living in Michigan with his third wife, Jan Rousseaux. Before meeting his current wife, he briefly dated Beth Twitter, mother of Natalee Holloway, who disappeared in Aruba in 2005.

Patsy passed away in 2006 at age 49. The former beauty queen was diagnosed with stage 4 ovarian cancer in 1993 and had been in remission for nine years before it returned in 2002.

JonBenét's older brother, Burke, attended Purdue University and graduated in 2009. According to a 2012 interview John gave to People, Burke was living a "pretty quiet" life with a girlfriend and a job in tech.

Where is JonBenét buried? Why isn't her grave in Colorado?

People who have sparked an interest in the case have often found themselves in Boulder, looking for JonBenét's grave, only to come up short. That's because she wasn't interred in Colorado. 

John Ramsey had three children from a previous marriage to Lucina Pasch. The couple divorced in 1978 and John married Patsy, born Patricia Paugh, in 1980. Four years before JonBenét's murder, John's eldest daughter, Elizabeth, died in a car crash at age 22 and was interred at St. James Episcopal Cemetery in Marietta, Georgia.

When JonBenét died, her body was transported to Georgia to be buried near Elizabeth. When Patsy died of ovarian cancer in 2006, she too was interred in Marietta alongside her daughter and her mother, Nedra Paugh, who preceded her in death in 2001.

Hunting JonBenét's Killer: The Untold Story premieres Thursday, April 11 at 9 p.m. on A&E.