IMPERIAL COUNTY, Calif.- For criminals in Imperial County there are a million places to disappear. The Valley stretches for miles with vast desert terrains, mountains, and fields. When a homicide happens, investigators follow every lead they can, but eventually some cases hit a dead end. The files are stored away, waiting for new evidence, a new witness, or a new break. "Witnesses' memories fade. They move, they change address, they change names.