Muoi Nguyen, known as Ni, was 29 when she vanished from Calgary, Alberta, in January 1990. Born in Vietnam, she had come to Canada from Thailand in the mid-1980s and worked downtown at a coffee shop and at La Quinta Fashions. Her family last saw her in January 1990 after she had recently ended a relationship with an intimate partner. She was later reported missing and never returned.

At the time of her disappearance her son, Gia Buu Phan, was seven and still in Vietnam; he arrived in Canada years later without his mother. The Calgary Police Service Missing Persons Team lists the case as active and has sought DNA from family members to check against unidentified remains. Investigators have asked anyone who knew Muoi or had contact with her around January 1990 to come forward.

Does anyone who lived or worked in downtown Calgary in 1990 remember Muoi or have information about her last days?