On October 12, 1986, the body of 27-year-old Cathleen Marian Cathy Thomas was found on the Colonial Parkway in York County, Virginia, alongside 21-year-old Rebecca Ann Dowski. Their vehicle had been pushed down an embankment and, inside and nearby, both women had been strangled and their throats slashed. Rope burns on both victims indicated they had been bound, and investigators concluded the murders may have occurred elsewhere before the car was moved to the Parkway.

Examination of the car produced more than 100 fingerprints, but none matched records available at the time. The killings were the first in a string of double homicides later dubbed the Colonial Parkway Murders. Over the years more than 150 people were questioned and cleared, and no arrests were ever announced in this pair of deaths.

A separate development in January 2024 linked another man to different Colonial Parkway killings, but officials said there was no forensic or physical evidence tying him to Thomas and Dowski. The murder of Cathleen Marian Cathy Thomas therefore remains unsolved.

If anyone knew Cathy, Rebecca, their routines, or saw anything on or near the Colonial Parkway in October 1986, please come forward with information.