Shelley Lynn Jones Mook was last seen around 3:30 Monday, Feb. 28, 2011, when she left work at Harris Middle School in Shelbyville, Tenn., and went to her ex-husband's house to drop off their daughter.
Her car was found a few hours later, burning in southeastern Rutherford County.
At first, the police thought the car was torched after a joyride, but then they traced it back to a missing woman.
In the years since she disappeared, speculation turned on ex-husband Tyler Mook, who had a history of domestic violence and refused to cooperate with the investigation.
Her disappearance briefly caught the nation's attention inspiring stories on CNN and a 48 Hours episode.
The media attention and eventual conviction of Tyler Mook on an unrelated crime hasn't eased the pain of Shelley Mook's family.
"I want the hurt to stop for those that have and are still affected by the acts of one person. Strength be to those who will stand and have their voices heard. It is by those voices that justice will come. By those voices, healing can begin, closure can be sought and faith in others can be restored," Shelley Mook's mother Debra Sikora said in 2014.
Anyone with information can call the Shelbyville Police Department at 931-684-5811 or the TBI at 1-800-TBI-FIND.
Shelley Mook was a 24-year-old single mother and teacher when she disappeared. She was described as standing 5'7" and weighing 135 pounds with blonde hair and blue eyes.
A native of Pennsylvania, she was described as "a beloved daughter, mother, sister and friend of many people" on the website FindShelley.com.
In only her second year of teaching, she taught eighth-grade reading and language arts at Harris Middle School in Bedford County.
"She has been an excellent teacher at Harris Middle and is well-liked by students and faculty," Bedford County Schools Superintendent Ed Gray told The Daily News Journal a few days after her disappearance. "My granddaughter had her last year and really liked her."
Mook was last seen Monday, Feb. 28, 2011, as she dropped her 6-year-old daughter at Tyler Mook's home on Old Nashville Dirt Road outside Shelbyville.
She was scheduled to meet a maintenance man at an apartment in Murfreesboro at 4:30 Monday afternoon but never showed.
The school teacher had taken a few days off work to move from Shelbyville to a new apartment in Murfreesboro.
She had a substitute teacher cover her classes that Monday and was supposed to return to work Wednesday. But Wednesday came and she didn't call in or didn't hire a substitute teacher, according to news reports at the time.
Her principal knew something was amiss because it was the first time she had missed work without letting someone know or hiring a substitute.
"By 8:30 a.m., they had exhausted ways of getting in touch with her," Gray said.
She was reported missing by her ex-husband Tyler Mook when she failed to pick up their daughter. Police asked the public to be on the lookout for a white four-door 2004 Pontiac Grand Prix.
The car was found Monday, Feb. 28, 2011, off Manchester Highway southeast of Murfreesboro fully engulfed in flame.
After it was traced back to Shelley Mook, it was taken by the TBI for forensic testing. TBI spokeswoman at the time Kristen Helm said there wasn't much of the car left, but the car was processed as a crime scene in case some evidence was left. All they were able to find was evidence of an accelerant likely used to start the fire.
Over the months, Shelbyville police searched behind Tyler Mook's home with cadaver dogs within a few weeks of her disappearance. They also performed land and water searches across Bedford County.
On March 8, 2011, a $10,000 reward was offered for information leading to Mook's whereabouts. The reward was increased to $20,000 in 2012.
In 2012, TBI searched a Franklin County rail yard for evidence but the search revealed nothing, according to the Times-Free Press.
They found no trace of Shelley Mook, according to reports in the Shelbyville Times-Gazette.
Early in the investigation, the TBI named Mook's ex-husband Tyler Mook as the main person of interest in her disappearance.
According to investigators with the Shelbyville Police Department, Tyler Mook was the last person to see her alive when she dropped off their daughter at his house.
Tyler and Shelley Mook met in Pennsylvania and moved to Bedford County soon after they married to be closer to his family. After six tumultuous years of marriage and a daughter, they divorced.
The child is being raised by Shelley Mook's mother after a custody battle barred "indefinitely" Tyler Mook and his family from contact with his daughter. The girl testified her father and grandfather talked to her about trying to burn down the home of Shelley Mook's mother.
Within a week of her disappearance, the TBI had obtained a search warrant and searched Tyler Mook's home for clues.
He has not cooperated with the investigation and has continually denied any knowledge or connection to Shelley Mook's disappearance.
In a separate incident, Tyler Mook was arrested in 2014 in Palm City, Fla. and charged with trying to kill his ex-girlfriend.
According to the Martin County, Fla., Sheriff's Office, Tyler Mook got into an argument with his girlfriend aboard a boat in October 2014 while on the Intercoastal Waterway. He pushed her into the water, then dove in after her and held her underwater in an apparent attempt to drown her.
A family member jumped in and separated the two. The girlfriend was able to swim away.
After the incident, Tyler Mook allegedly said to a witness "No one disrespects me in front of my family. I will kill her."
In 2016, Tyler Mook was convicted of attempted first-degree murder and sentenced to 12 years.
With no activity on her credit cards and bank account, investigators assume that Shelley Mook was killed.
Brooks has said she doesn't believe Shelley Mook would have left her daughter voluntarily.
Investigators ruled out the maintenance man and another man Shelley Mook had just started dating, which left Tyler Mook as the main suspect.
Friends and family said Tyler Mook was "abusive, at times cruel" to his ex-wife and that there was a record of domestic violence.
Private investigator Kevin Keele, who was hired by Shelley Mook's family to look into the case, recounted the testimony of Mook's daughter.
"The version (she) told early on, Shelley got out of the car, went to the door, left her in the car seat," Keele said in a 2017 interview with Crime Watch Daily. "Shelley went inside with Tyler. At some point, Tyler came back outside, got her out of her car seat, took her to her old bedroom. She said she never saw her mother when she came into the residence, into the bedroom."
In 2014, Keele said he believes whoever killed Shelley Mook didn't work alone.
"There absolutely would have had to have been help in disposing of her vehicle," Keele said in an interview with WSMV.
It would have been impossible for a single person to drive the car from Shelbyville to the outskirts of Murfreesboro without a ride away from the scene, Keele said.
Shelley Mook's friends and family are convinced Tyler Mook is responsible for her death.
“He definitely needs to pay for what he did to her. He needs to serve his time for what he did to her. No family should ever have to go through this," Shelley Mook’s friend Brittany Brooks said in 2016.