On February 15, 1976, the bodies of two 14-year-old girls were found under the Happy Valley Overpass on Highway 1 just west of Calgary. Patricia Marie McQueen, known as Patsy, and her friend Eva Dvorak had last been seen the previous day after being sent home from Ian Bazalgette Junior High for drinking at school; a passerby discovered their bodies the next morning. Autopsy testing showed alcohol and drugs in their systems, but no definitive cause of death was determined at the time and the scene suggested the girls had been dumped beneath the overpass.

Decades of tips produced no arrest, but forensic advances reopened the files. DNA from both victims matched the same unknown male profile linked to other Calgary-area murders; in 2024 the Alberta RCMP Historical Homicide Unit, with Interpol and Idaho State Police, matched that profile to deceased American offender Gary Allen Srery. Srery fled the U.S. in 1974 and died in an Idaho prison in 2011. Authorities say they believe he may be connected to additional unsolved Western Canada homicides and continue to investigate.