Mariella Lennie was a 17-year-old Indigenous woman from Tulita, Northwest Territories, who moved to Yellowknife in the fall of 1991 to continue her education and left her four-month-old baby with her parents. She was last seen on October 6, 1991 leaving the Discovery Inn on 50 Avenue in downtown Yellowknife at about 6 p.m., reportedly alone and on foot. Twelve days later she was reported missing after friends and family could not locate her.

On May 8, 1992 her badly decomposed remains were recovered floating in Great Slave Lake near the former Con Mine in Yellowknife Bay and were identified by dental records. Medical notes obtained by her aunt described her as found partially clothed, with her jeans open and pulled down, no shirt, one shoe missing, and a mark or injury on her head. Police treated the circumstances as suspicious and did not eliminate foul play, but publicly withheld an official cause of death; reporting describes the matter as a homicide investigation.

Investigators examined several people who had been in her life, and some were later ruled out using techniques including polygraph examinations, but no one has been publicly identified as responsible and there have been no charges. The family continues to seek answers. Did anyone in Yellowknife or Tulita at that time have information about who Mariella was with on the night of October 6, 1991?