Before the Outbreak, Jack Sheppard was a Cop. Traffic stops, domestics, court hearings, writing citations.
When the outbreak in Western Europe broke out saw this as an opportunity to escape the repetitive norm that had become his life. He took some leave and signed up to help with the relief effort in Chernarus, helping to run food and medical supplies between the towns stretched across the countryside. Upon arrival, the military would not allow the civilian agency he had signed up with off the Airbase to help, nor were they letting anybody leave to return home. Stuck there, trapped with refugees and volunteers alike they waited for the military to let them return home, but before any action could be taken the infected over-ran the Airfield Jack was being held at and in the chaos found himself running alone through the Chernarussian countryside, trying to survive like everybody else by whatever means necessary.