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Case Description

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Theresa Lamontagne, a 29-year-old woman from Roseville, Michigan, was last seen on September 29, 2003. After getting off work, she went to her mother�s house in Roseville and made several calls trying to arrange a ride back to her home in New Haven. She was awaiting a family friend to pick her up, but when they called to inform her they were on their way, Theresa was no longer there and has not been seen since. At the time of her disappearance, she was wearing medical scrubs and gym shoes, and s ...Read More
Last Seen: Sep 29, 2003

Victim Details

May 15, 2018

Apr 21, 2022

Theresa

Lamontagne

50

29

69 inches

71 inches

145 lbs

155 lbs

White / Caucasian

Female

On a Monday in the fall of 2003, a 29-year-old mother named Theresa Marie Lamontagne finished her workday and went to her mother's house in Roseville, Michigan. It was September 29th, and Theresa, a resident of nearby New Haven, needed a ride home. Dressed in her medical scrubs and gym shoes, she began calling people to arrange transportation. The day was marked by a sense of unease, as Theresa expressed to her mother that she was feeling overwhelmed, stating, "Everything's getting to me, Mama. I gotta get away." While she was waiting for a family friend to pick her up, she vanished. In one version of events, the friend called to say they were on the way, but Theresa was nowhere to be found when they arrived. Another account of her last known moments came from her brother, who was in another room at their mother's house. He reported hearing the front door slam and hurried to a window just in time to see his sister get into the passenger side of a white sedan. The car, which was unfamiliar to the family, had an unknown individual at the wheel and drove away, carrying Theresa into a mystery that has now spanned decades. Her family has not seen or heard from her since that moment. At the time of her disappearance, Theresa was described as a tall woman with sandy hair, green eyes, a scar above one of her eyes, and a tattoo on her thigh. In the weeks and months that followed, Theresa�s family was left grappling with her sudden absence. Her twin sister, Julie Morosky, was haunted by questions and disturbing dreams about her sister's fate. The family acknowledged that Theresa had been under significant stress from her job, financial pressures, and a volatile relationship with her boyfriend, who had a past domestic assault charge. While Theresa had a history of leaving for short periods when feeling overwhelmed, her loved ones insisted this time was different. They stated she had never been out of contact for more than a week and would never have abandoned her three children, for whom she cared deeply. Law enforcement at the time, however, considered the possibility that she had left voluntarily. They received a tip that she may have run off with another man she was seeing. Despite this, the case remained an active missing person investigation as police acknowledged they had exhausted nearly all leads. The investigation into Theresa Lamontagne's disappearance has left more questions than answers. The conflicting accounts of her last moments�whether she was waiting for a ride that arrived too late or if she left in a mysterious white car�complicate the narrative. Her family remains convinced that she would not have willingly cut off all contact, pointing to her strong maternal bonds as evidence that something tragic must have occurred. Law enforcement's initial theory that she may not have wanted to be found has, over the years, transitioned into a long-standing cold case. Without any definitive evidence of her whereabouts or what happened after she left her mother's home, the case of Theresa Lamontagne remains an unresolved and sorrowful mystery for her children, her twin sister, and the rest of her family who are still awaiting answers.

Sep 29, 2003

Roseville

Michigan

Macomb County

35221

Macomb County Sheriff's Office

Mt. Clemens

Michigan

Macomb County

48043

Ryan Ruttan

Detective

43565 Elizabeth Rd., Michigan

5864695151

County

Law Enforcement

03-2701

Macomb County Sheriff's Office

10432

Sandy

Green

Green

06/03/2026


Area Last Seen: