In 1987, teenage sweethearts Tanya Van Cuylenborg and Jay Cook set out from Victoria, BC for a one-night trip to Seattle. Tragically they were never seen alive again. Somewhere along their route they encountered a violent stranger who targeted the trusting couple. But who was this evil predator, and would he strike again? The killer had left his DNA at the crime scene but with limited forensic testing available in 1987, the double murder case went cold. Many years passed before advances in genetic testing gave investigators an exciting new approach to potentially finding the killer. Could a stranger’s DNA profile on a public ancestry database be the key to solving a double murder?