Mary Lynn Witherspoon, the Charleston, South Carolina, school teacher who was found strangled to death in her bathtub 13 years ago, will have her case documented on tonight’s Obsession: Dark Desires on Investigation Discovery (ID).

Every week, Obsession: Dark Desires profiles a new tragic story of obsession that escalated to murder. The episode featuring the case of Mary Lynn Witherspoon and her killer, Edmonds Tennent Brown, is called, “There’s Something About Mary.” For the teacher’s death, Tennent Brown is serving a life sentence in a South Carolina correctional facility.

Fifty-two-year-old Mary Lynn Witherspoon was found dead in November 2003. The day that she was discovered, she had been reported missing after not showing up to her teaching job at Charlestowne Academy, where she taught French. Authorities say upon entering the home located in downtown Charleston at 165 Tadd Street, they found items strewn about the foyer, where it appeared the struggle ensued. As they made their way up the stairs and into the master bathroom, they found the teacher’s body inside of the bathtub. An autopsy report concluded that she had been strangled.

An investigation into her killing revealed that Mary Lynn Witherspoon had endured years of stalking by Edmonds Tennent Brown, a 32-year-old man that she had known since he was the age of 10. Police say Witherspoon dated the killer’s father for almost a decade. People who knew Tennent Brown said that he was a very strange person who craved attention from Mary Lynn Witherspoon, even as a child. His family didn’t get him the help that he needed back then, and by the time he was a teenager, he had serious mental issues and acted out by getting into trouble with the law, according to Dateline NBC, which covered the case in the 2006 episode “The Murder of a Lovely Teacher.”

Always a kind and giving person, Mary Lynn Witherspoon tried to give Edmonds Tennent Brown the benefit of the doubt, since she had known him for so long and had cared deeply for his father. But, over time, the situation became downright scary. It was like watching another person’s bizarre story, and at first, Mary Lynn refused to call the police. She thought she could handle it herself by installing a new security system and by purchasing pepper spray to protect herself. But by then, the situation had escalated out of control, and Edmonds Tennent Brown was no longer standing outside on the sidewalk but was making his way onto her property.

Sometimes she would return home and find him in her backyard. He also stole her overnight bag on occasion and broke into her laundry room and stole her panties on another occasion.

Family members were begging the teacher to stop living in fear and call the police. She finally did press charges, and Tennent Brown was arrested for burglary. Those several months that he was in jail gave her some peace of mind, and she had signed up to South Carolina’s VINE system, a notification system that alerts victims of a criminal’s upcoming release. However, when it was time for Tennent Brown to be released, Mary Lynn Witherspoon never received the notification. Sadly, he killed her soon after he was free.

Even after he killed her, Tennent Brown, who was diagnosed as bipolar, had to return to the scene just one more time. Police found him walking along the sidewalk in front of her home. When he was arrested, he was wearing Mary Lynn Witherspoon’s underwear and pants. Authorities say that other items found in his possession showed that his intention was to take over Mary Lynn Witherspoon’s identity. He wanted to become her.

To watch how the Mary Lynn Witherspoon/Tennent Brown fatal attraction story unfolded, watch Obsession: Dark Desire’s coverage tonight at 9/8 p.m. central on Investigation Discovery.

[Image via YouTube, South Carolina Department of Corrections]